<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }

    body {
      background: #f8fafc;
      color: #1e293b;
      padding: 16px;
      display: flex;
      flex-direction: column;
      gap: 16px;
      user-select: none;
    }

    /* Problem Story Box */
    .story-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 18px 20px;
      font-size: 17px;
      line-height: 1.7;
      color: #334155;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
    }

    .hl {
      display: inline-block;
      padding: 2px 8px;
      border-radius: 6px;
      font-weight: 600;
      cursor: pointer;
      transition: all 0.25s ease;
      border: 1.5px solid transparent;
    }

    .hl-known {
      background: #dcfce7;
      color: #15803d;
      border-color: #86efac;
    }

    .hl-unknown {
      background: #e0f2fe;
      color: #0369a1;
      border-color: #7dd3fc;
    }

    .hl.active {
      box-shadow: 0 0 0 3px rgba(34, 183, 255, 0.35);
      transform: translateY(-1px);
    }

    /* Breakdown Grid */
    .badges-container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }

    @media (max-width: 480px) {
      .badges-container {
        grid-template-columns: 1fr;
      }
      .story-card {
        font-size: 15px;
        padding: 14px 16px;
      }
    }

    .badge-card {
      background: #ffffff;
      border-radius: 12px;
      padding: 14px 16px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      cursor: pointer;
      transition: all 0.25s ease;
      border: 2px solid transparent;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
    }

    .badge-known {
      border-color: #bbf7d0;
      background: #f0fdf4;
    }

    .badge-unknown {
      border-color: #bae6fd;
      background: #f0f9ff;
    }

    .badge-card.active {
      box-shadow: 0 0 0 3px rgba(34, 183, 255, 0.4);
      transform: translateY(-2px);
    }

    .badge-header {
      display: flex;
      align-items: center;
      gap: 6px;
      font-size: 13px;
      font-weight: 700;
      letter-spacing: 0.5px;
      text-transform: uppercase;
    }

    .badge-known .badge-header {
      color: #166534;
    }

    .badge-unknown .badge-header {
      color: #075985;
    }

    .tag-list {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
    }

    .item-tag {
      background: #ffffff;
      padding: 4px 10px;
      border-radius: 6px;
      font-size: 14px;
      font-weight: 600;
      border: 1px solid rgba(0,0,0,0.08);
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    .badge-known .item-tag {
      color: #15803d;
      border-color: #86efac;
    }

    .badge-unknown .item-tag {
      color: #0369a1;
      border-color: #7dd3fc;
      background: #ffffff;
    }

    /* Connecting cue line */
    .connector-hint {
      text-align: center;
      font-size: 12px;
      color: #64748b;
      font-weight: 500;
    }
  </style>
</head>
<body>

  
  <div class="story-card">
    Leo buys 
    <span class="hl hl-known" data-group="known">3 packs of stickers</span>. 
    There are 
    <span class="hl hl-known" data-group="known">6 stickers in each pack</span>. 
    He gives 
    <span class="hl hl-known" data-group="known">4 stickers</span> to his friend. 
    <span class="hl hl-unknown" data-group="unknown">How many stickers does Leo have left?</span>
  </div>

  
  <div class="badges-container">
    
    <div class="badge-card badge-known" data-group="known">
      <div class="badge-header">
        <span>✓</span> Known Values
      </div>
      <div class="tag-list">
        <span class="item-tag">📦 3 packs</span>
        <span class="item-tag">✨ 6 per pack</span>
        <span class="item-tag">🎁 4 given away</span>
      </div>
    </div>

    
    <div class="badge-card badge-unknown" data-group="unknown">
      <div class="badge-header">
        <span>✦</span> Target Unknown
      </div>
      <div class="tag-list">
        <span class="item-tag">❓ Leftover stickers</span>
      </div>
    </div>
  </div>

  <div class="connector-hint">Tap any highlighted section to see where it belongs</div>

  <script>
    const knownElements = document.querySelectorAll('[data-group="known"]');
    const unknownElements = document.querySelectorAll('[data-group="unknown"]');

    function setActiveGroup(group) {
      document.querySelectorAll('.active').forEach(el => el.classList.remove('active'));
      if (group === 'known') {
        knownElements.forEach(el => el.classList.add('active'));
      } else if (group === 'unknown') {
        unknownElements.forEach(el => el.classList.add('active'));
      }
    }

    document.querySelectorAll('[data-group]').forEach(el => {
      el.addEventListener('click', (e) => {
        const group = el.getAttribute('data-group');
        setActiveGroup(group);
      });
    });
  </script>
</body>
</html>

Finding What You Know and What You Need in Word Problems

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, sans-serif;
      user-select: none;
    }

    body {
      width: 100%;
      min-height: 100%;
      background: #f8fafc;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 12px;
      gap: 12px;
    }

    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 4px;
    }

    .tab-btn {
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      border-radius: 9999px;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #64748b;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .tab-btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
      box-shadow: 0 2px 6px rgba(2, 132, 199, 0.25);
    }

    .flow-container {
      display: flex;
      flex-direction: column;
      gap: 12px;
      width: 100%;
      max-width: 480px;
      align-items: center;
    }

    @media (min-width: 520px) {
      .flow-container {
        flex-direction: row;
        align-items: stretch;
      }
    }

    .step-box {
      flex: 1;
      width: 100%;
      background: #ffffff;
      border: 2px solid #e2e8f0;
      border-radius: 14px;
      padding: 14px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      gap: 10px;
      transition: opacity 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
    }

    .step-box.highlight {
      border-color: #0284c7;
      box-shadow: 0 4px 12px rgba(2, 132, 199, 0.12);
    }

    .step-box.dimmed {
      opacity: 0.4;
    }

    .step-tag {
      font-size: 11px;
      font-weight: 700;
      letter-spacing: 0.05em;
      text-transform: uppercase;
      padding: 3px 8px;
      border-radius: 6px;
      background: #f1f5f9;
      color: #475569;
    }

    .step-box.highlight .step-tag {
      background: #e0f2fe;
      color: #0369a1;
    }

    /* Step 1 Visuals */
    .packs-row {
      display: flex;
      gap: 8px;
      justify-content: center;
      align-items: center;
    }

    .pack {
      background: #f0f9ff;
      border: 1.5px dashed #0284c7;
      border-radius: 8px;
      padding: 6px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 2px;
      min-width: 42px;
    }

    .pack-icon {
      font-size: 18px;
    }

    .pack-count {
      font-size: 12px;
      font-weight: 700;
      color: #0284c7;
    }

    /* Step 2 Visuals */
    .stickers-grid {
      display: grid;
      grid-template-columns: repeat(6, 1fr);
      gap: 4px;
      padding: 4px;
    }

    .sticker-item {
      font-size: 14px;
      line-height: 1;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
    }

    .sticker-item.removed {
      opacity: 0.45;
      filter: grayscale(0.5);
    }

    .sticker-item.removed::after {
      content: '✕';
      position: absolute;
      font-size: 13px;
      font-weight: 900;
      color: #dc2626;
    }

    /* Equation Bar */
    .equation {
      font-size: 15px;
      font-weight: 700;
      color: #0f172a;
      display: flex;
      align-items: center;
      gap: 6px;
      background: #f8fafc;
      padding: 6px 12px;
      border-radius: 8px;
      border: 1px solid #e2e8f0;
    }

    .result-badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: #22c55e;
      color: #ffffff;
      border-radius: 6px;
      padding: 2px 6px;
      font-size: 14px;
      gap: 3px;
    }

    .bridge-num {
      background: #e0f2fe;
      color: #0369a1;
      padding: 1px 6px;
      border-radius: 4px;
    }

    .connector-arrow {
      font-size: 20px;
      color: #0284c7;
      font-weight: 800;
      transform: rotate(90deg);
      display: flex;
      align-items: center;
      justify-content: center;
    }

    @media (min-width: 520px) {
      .connector-arrow {
        transform: rotate(0deg);
      }
    }
  </style>
</head>
<body>

  <div class="controls">
    <button class="tab-btn" id="btn-step1" onclick="setStep(1)">Step 1</button>
    <button class="tab-btn" id="btn-step2" onclick="setStep(2)">Step 2</button>
    <button class="tab-btn active" id="btn-all" onclick="setStep(0)">All</button>
  </div>

  <div class="flow-container">
    
    <div class="step-box" id="card-step1">
      <span class="step-tag">Step 1: Hidden Total</span>
      
      <div class="packs-row">
        <div class="pack">
          <span class="pack-icon">🏷️</span>
          <span class="pack-count">6</span>
        </div>
        <div class="pack">
          <span class="pack-icon">🏷️</span>
          <span class="pack-count">6</span>
        </div>
        <div class="pack">
          <span class="pack-icon">🏷️</span>
          <span class="pack-count">6</span>
        </div>
      </div>

      <div class="equation">
        3 × 6 = <span class="bridge-num">18</span>
      </div>
    </div>

    <div class="connector-arrow">➔</div>

    
    <div class="step-box" id="card-step2">
      <span class="step-tag">Step 2: Target Unknown</span>
      
      <div class="stickers-grid" id="grid">
        
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        <span class="sticker-item">⭐</span>
        
        <span class="sticker-item removed">⭐</span>
        <span class="sticker-item removed">⭐</span>
        <span class="sticker-item removed">⭐</span>
        <span class="sticker-item removed">⭐</span>
      </div>

      <div class="equation">
        <span class="bridge-num">18</span> − 4 = 
        <span class="result-badge">✓ 14</span>
      </div>
    </div>
  </div>

  <script>
    function setStep(step) {
      const c1 = document.getElementById('card-step1');
      const c2 = document.getElementById('card-step2');
      const b1 = document.getElementById('btn-step1');
      const b2 = document.getElementById('btn-step2');
      const bAll = document.getElementById('btn-all');

      b1.classList.remove('active');
      b2.classList.remove('active');
      bAll.classList.remove('active');

      if (step === 1) {
        b1.classList.add('active');
        c1.classList.add('highlight');
        c1.classList.remove('dimmed');
        c2.classList.remove('highlight');
        c2.classList.add('dimmed');
      } else if (step === 2) {
        b2.classList.add('active');
        c2.classList.add('highlight');
        c2.classList.remove('dimmed');
        c1.classList.remove('highlight');
        c1.classList.add('dimmed');
      } else {
        bAll.classList.add('active');
        c1.classList.remove('dimmed', 'highlight');
        c2.classList.remove('dimmed', 'highlight');
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      user-select: none;
      -webkit-user-select: none;
    }

    body {
      background: #ffffff;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 12px 16px;
    }

    .nav-bar {
      display: flex;
      gap: 8px;
      margin-bottom: 8px;
      z-index: 10;
    }

    .step-btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 20px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .step-btn.active {
      background: #2563eb;
      border-color: #2563eb;
      color: #ffffff;
    }

    .diagram-wrap {
      width: 100%;
      max-width: 520px;
      aspect-ratio: 520 / 340;
      position: relative;
    }

    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    .bracket {
      fill: none;
      stroke: #64748b;
      stroke-width: 2;
      stroke-linecap: round;
      stroke-linejoin: round;
    }

    .guide-line {
      stroke: #94a3b8;
      stroke-dasharray: 4 4;
      stroke-width: 1.5;
      opacity: 0.7;
    }

    .bar-rect {
      stroke: #1e2945;
      stroke-width: 2;
      transition: fill 0.3s ease, stroke 0.3s ease;
    }

    .text-main {
      font-size: 15px;
      font-weight: 700;
      fill: #1e2945;
      text-anchor: middle;
      dominant-baseline: central;
    }

    .text-title {
      font-size: 14px;
      font-weight: 700;
      fill: #2563eb;
      text-anchor: middle;
      dominant-baseline: central;
    }

    .text-sub {
      font-size: 13px;
      font-weight: 600;
      fill: #64748b;
      text-anchor: middle;
      dominant-baseline: central;
    }

    .badge {
      transition: opacity 0.3s ease, transform 0.3s ease;
    }

    .step2-el {
      transition: opacity 0.4s ease;
    }
  </style>
</head>
<body>

  <div class="nav-bar">
    <button class="step-btn" id="btn-step1" onclick="setStep(1)">Step 1: Total</button>
    <button class="step-btn" id="btn-step2" onclick="setStep(2)">Step 2: Leftover</button>
    <button class="step-btn active" id="btn-all" onclick="setStep(3)">Both Steps</button>
  </div>

  <div class="diagram-wrap">
    <svg viewBox="0 0 520 340">
      
      <g id="step1-group">
        
        <path class="bracket" d="M 60,75 L 60,65 Q 60,55 70,55 L 250,55 Q 260,55 260,45 Q 260,55 270,55 L 450,55 Q 460,55 460,65 L 460,75" />
        
        
        <text class="text-title" x="260" y="28" id="top-total-label">Total = ? (18)</text>

        
        
        <rect class="bar-rect" x="60" y="80" width="133.3" height="52" rx="4" fill="#fed7aa" />
        <text class="text-main" x="126.6" y="106">6</text>

        
        <rect class="bar-rect" x="193.3" y="80" width="133.3" height="52" rx="4" fill="#fed7aa" />
        <text class="text-main" x="260" y="106">6</text>

        
        <rect class="bar-rect" x="326.6" y="80" width="133.4" height="52" rx="4" fill="#fed7aa" />
        <text class="text-main" x="393.3" y="106">6</text>
      </g>

      
      <g id="connectors" class="step2-el">
        <line class="guide-line" x1="60" y1="135" x2="60" y2="200" />
        <line class="guide-line" x1="460" y1="135" x2="460" y2="200" />
        <text class="text-sub" x="260" y="168" style="font-size:12px; letter-spacing:0.5px;">Hidden Value = 18</text>
      </g>

      
      <g id="step2-group" class="step2-el">
        
        <rect class="bar-rect" x="60" y="205" width="88.9" height="52" rx="4" fill="#fee2e2" stroke="#dc2626" />
        <text class="text-main" x="104.4" y="226" style="fill:#b91c1c; font-size:14px;">4</text>
        <text class="text-sub" x="104.4" y="243" style="fill:#dc2626; font-size:11px;">given</text>

        
        <rect class="bar-rect" x="148.9" y="205" width="311.1" height="52" rx="4" fill="#bae6fd" stroke="#0284c7" />
        <text class="text-main" x="304.4" y="231" style="fill:#0369a1; font-size:16px;">?  (14)</text>

        
        <path class="bracket" stroke="#0284c7" d="M 149,265 L 149,275 Q 149,285 159,285 L 294,285 Q 304,285 304,295 Q 304,285 314,285 L 450,285 Q 460,285 460,275 L 460,265" />
        <text class="text-title" x="304" y="318" style="fill:#0284c7;">Leftover = 14</text>
      </g>
    </svg>
  </div>

  <script>
    function setStep(step) {
      document.querySelectorAll('.step-btn').forEach(btn => btn.classList.remove('active'));
      
      const s2Els = document.querySelectorAll('.step2-el');
      const topTotal = document.getElementById('top-total-label');
      
      if (step === 1) {
        document.getElementById('btn-step1').classList.add('active');
        s2Els.forEach(el => el.style.opacity = '0.08');
        topTotal.textContent = 'Total = ? (6 × 3 = 18)';
      } else if (step === 2) {
        document.getElementById('btn-step2').classList.add('active');
        s2Els.forEach(el => el.style.opacity = '1');
        topTotal.textContent = 'Total = 18';
      } else {
        document.getElementById('btn-all').classList.add('active');
        s2Els.forEach(el => el.style.opacity = '1');
        topTotal.textContent = 'Total = ? (Hidden Value: 18)';
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }
    
    .nav-tabs {
      display: flex;
      gap: 6px;
      width: 100%;
      max-width: 520px;
      margin-bottom: 10px;
    }
    .tab-btn {
      flex: 1;
      border: 1px solid #d1d5db;
      background: #ffffff;
      color: #4b5563;
      padding: 8px 4px;
      font-size: 13px;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
      white-space: nowrap;
    }
    .tab-btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
      box-shadow: 0 2px 6px rgba(2, 132, 199, 0.25);
    }

    .stage-container {
      position: relative;
      width: 100%;
      max-width: 520px;
      height: 250px;
      overflow: hidden;
    }

    .step-card {
      position: absolute;
      inset: 0;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.35s ease, transform 0.35s ease;
      transform: translateY(8px);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 14px 16px;
    }
    .step-card.active {
      opacity: 1;
      pointer-events: auto;
      transform: translateY(0);
    }

    .card-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .badge {
      font-size: 12px;
      font-weight: 700;
      padding: 3px 8px;
      border-radius: 6px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .badge-known { background: #e0f2fe; color: #0369a1; }
    .badge-hidden { background: #fef3c7; color: #b45309; }
    .badge-target { background: #dcfce7; color: #15803d; }

    .formula {
      font-size: 18px;
      font-weight: 700;
      color: #0f172a;
    }

    .visual-area {
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 8px 0;
    }

    /* Visual 1: Trays */
    .trays-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 8px;
      width: 100%;
      max-width: 380px;
    }
    .tray {
      background: #e2e8f0;
      border: 2px solid #cbd5e1;
      border-radius: 8px;
      padding: 6px 4px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
    }
    .cookie-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2.5px;
    }
    .cookie-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #d97706;
    }
    .tray-lbl {
      font-size: 11px;
      font-weight: 700;
      color: #475569;
    }

    /* Visual 2: Multiplication Grouping */
    .calc-row {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
    }
    .calc-box {
      background: #ffffff;
      border: 1.5px solid #cbd5e1;
      border-radius: 10px;
      padding: 10px 14px;
      text-align: center;
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    }
    .calc-num {
      font-size: 20px;
      font-weight: 800;
      color: #0284c7;
    }
    .calc-sub {
      font-size: 12px;
      color: #64748b;
      font-weight: 600;
    }
    .op {
      font-size: 20px;
      font-weight: 800;
      color: #94a3b8;
    }

    /* Visual 3: Subtraction bar */
    .remain-flow {
      display: flex;
      align-items: center;
      gap: 10px;
      width: 100%;
      max-width: 420px;
    }
    .bar-col {
      flex: 1;
      background: #ffffff;
      border-radius: 8px;
      border: 1.5px solid #e2e8f0;
      padding: 8px;
      text-align: center;
    }
    .bar-sold {
      background: #fee2e2;
      border-color: #fca5a5;
    }
    .bar-left {
      background: #dcfce7;
      border-color: #86efac;
    }
    .val-main {
      font-size: 18px;
      font-weight: 800;
    }
    .sold-val { color: #dc2626; }
    .left-val { color: #16a34a; }
    .val-lbl {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
    }

    .card-footer {
      font-size: 13px;
      color: #334155;
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 6px;
      background: #ffffff;
      padding: 6px 10px;
      border-radius: 6px;
      border: 1px solid #e2e8f0;
    }

    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      margin-top: 10px;
      width: 100%;
      max-width: 520px;
    }
    .ctrl-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      color: #334155;
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .ctrl-btn:active {
      background: #f1f5f9;
    }
    .dots {
      display: flex;
      gap: 6px;
    }
    .dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      transition: background 0.2s;
    }
    .dot.active {
      background: #0284c7;
      transform: scale(1.15);
    }
  </style>
</head>
<body>

  <div class="nav-tabs">
    <button class="tab-btn active" id="tab0" onclick="setStep(0)">1. Knowns</button>
    <button class="tab-btn" id="tab1" onclick="setStep(1)">2. Hidden Step</button>
    <button class="tab-btn" id="tab2" onclick="setStep(2)">3. Target Goal</button>
  </div>

  <div class="stage-container">
    
    <div class="step-card active" id="step0">
      <div class="card-header">
        <span class="badge badge-known">Given Facts</span>
        <span class="formula">4 Trays • 12 Each • 30 Sold</span>
      </div>
      <div class="visual-area">
        <div class="trays-grid">
          <div class="tray">
            <div class="cookie-grid">
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
            </div>
            <span class="tray-lbl">12</span>
          </div>
          <div class="tray">
            <div class="cookie-grid">
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
            </div>
            <span class="tray-lbl">12</span>
          </div>
          <div class="tray">
            <div class="cookie-grid">
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
            </div>
            <span class="tray-lbl">12</span>
          </div>
          <div class="tray">
            <div class="cookie-grid">
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
              <span class="cookie-dot"></span><span class="cookie-dot"></span><span class="cookie-dot"></span>
            </div>
            <span class="tray-lbl">12</span>
          </div>
        </div>
      </div>
      <div class="card-footer">
        <span>🍪</span> 4 trays of 12 cookies baked; 30 cookies sold
      </div>
    </div>

    
    <div class="step-card" id="step1">
      <div class="card-header">
        <span class="badge badge-hidden">Hidden Question</span>
        <span class="formula">4 × 12 = 48 Total</span>
      </div>
      <div class="visual-area">
        <div class="calc-row">
          <div class="calc-box">
            <div class="calc-num">4</div>
            <div class="calc-sub">trays</div>
          </div>
          <div class="op">×</div>
          <div class="calc-box">
            <div class="calc-num">12</div>
            <div class="calc-sub">per tray</div>
          </div>
          <div class="op">=</div>
          <div class="calc-box" style="border-color: #f59e0b; background: #fffbeb;">
            <div class="calc-num" style="color: #b45309;">48</div>
            <div class="calc-sub">total baked</div>
          </div>
        </div>
      </div>
      <div class="card-footer">
        <span>✦</span> Bridge step: find total cookies before subtracting
      </div>
    </div>

    
    <div class="step-card" id="step2">
      <div class="card-header">
        <span class="badge badge-target">Target Unknown</span>
        <span class="formula">48 − 30 = 18 Left</span>
      </div>
      <div class="visual-area">
        <div class="remain-flow">
          <div class="bar-col">
            <div class="val-main">48</div>
            <div class="val-lbl">Total Baked</div>
          </div>
          <div class="op">−</div>
          <div class="bar-col bar-sold">
            <div class="val-main sold-val">30</div>
            <div class="val-lbl">Sold</div>
          </div>
          <div class="op">=</div>
          <div class="bar-col bar-left">
            <div class="val-main left-val">18</div>
            <div class="val-lbl">Cookies Left</div>
          </div>
        </div>
      </div>
      <div class="card-footer">
        <span>✓</span> Final solution found using the hidden bridge
      </div>
    </div>
  </div>

  <div class="controls">
    <button class="ctrl-btn" onclick="prevStep()">◀</button>
    <div class="dots">
      <div class="dot active" id="dot0" onclick="setStep(0)"></div>
      <div class="dot" id="dot1" onclick="setStep(1)"></div>
      <div class="dot" id="dot2" onclick="setStep(2)"></div>
    </div>
    <button class="ctrl-btn" onclick="nextStep()">▶</button>
  </div>

  <script>
    let current = 0;
    const total = 3;
    let timer = null;

    function setStep(idx) {
      current = idx;
      for (let i = 0; i < total; i++) {
        const card = document.getElementById('step' + i);
        const tab = document.getElementById('tab' + i);
        const dot = document.getElementById('dot' + i);
        if (i === current) {
          card.classList.add('active');
          tab.classList.add('active');
          dot.classList.add('active');
        } else {
          card.classList.remove('active');
          tab.classList.remove('active');
          dot.classList.remove('active');
        }
      }
    }

    function nextStep() {
      setStep((current + 1) % total);
      resetAuto();
    }

    function prevStep() {
      setStep((current - 1 + total) % total);
      resetAuto();
    }

    function startAuto() {
      timer = setInterval(() => {
        setStep((current + 1) % total);
      }, 4000);
    }

    function resetAuto() {
      clearInterval(timer);
      startAuto();
    }

    startAuto();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }

    body {
      width: 100%;
      min-height: 100%;
      background: #f8fafc;
      color: #1e2945;
      padding: 14px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .story-card {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px 14px;
      text-align: center;
      font-size: 15px;
      line-height: 1.6;
      font-weight: 500;
      color: #334155;
    }

    .chip {
      display: inline-block;
      padding: 2px 7px;
      border-radius: 6px;
      font-weight: 700;
      font-size: 14px;
      transition: opacity 0.2s ease, transform 0.2s ease;
      cursor: pointer;
    }

    .chip-ignore {
      background: #fee2e2;
      color: #b91c1c;
      border: 1px solid #fca5a5;
    }

    .chip-keep {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #86efac;
    }

    .columns {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
      width: 100%;
    }

    .column {
      background: #ffffff;
      border-radius: 12px;
      padding: 10px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .col-keep {
      border: 1.5px solid #86efac;
      background: #f0fdf4;
    }

    .col-ignore {
      border: 1.5px solid #fca5a5;
      background: #fef2f2;
    }

    .col-header {
      font-size: 13px;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      text-align: center;
      padding-bottom: 4px;
    }

    .col-keep .col-header {
      color: #15803d;
    }

    .col-ignore .col-header {
      color: #b91c1c;
    }

    .item-card {
      background: #ffffff;
      border-radius: 8px;
      padding: 8px 10px;
      font-size: 14px;
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      cursor: pointer;
    }

    .item-card.highlight {
      box-shadow: 0 0 0 2px #22b7ff;
    }

    .icon-keep {
      color: #16a34a;
      font-size: 16px;
      font-weight: 900;
    }

    .icon-ignore {
      color: #dc2626;
      font-size: 16px;
      font-weight: 900;
    }

    .math-bar {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 8px 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 600;
      color: #1e2945;
    }

    .math-eq {
      font-weight: 800;
      color: #15803d;
      background: #dcfce7;
      padding: 2px 8px;
      border-radius: 6px;
    }

    @media (max-width: 380px) {
      body {
        padding: 8px;
        gap: 8px;
      }
      .story-card {
        font-size: 14px;
        padding: 8px 10px;
      }
      .col-header {
        font-size: 11px;
      }
      .item-card {
        font-size: 13px;
        padding: 6px 8px;
      }
      .math-bar {
        font-size: 13px;
        padding: 6px 8px;
      }
    }
  </style>
</head>
<body>

  
  <div class="story-card">
    On <span class="chip chip-ignore" data-target="tuesday">Tuesday</span> at <span class="chip chip-ignore" data-target="time">3:00 PM</span>, Leo bought <span class="chip chip-keep" data-target="packs">3 packs</span> of <span class="chip chip-keep" data-target="stickers">6 stickers</span>.
  </div>

  
  <div class="columns">
    
    <div class="column col-keep">
      <div class="col-header">Salient Data (Keep!)</div>
      <div class="item-card" id="card-packs">
        <span class="icon-keep">✓</span>
        <span>3 packs</span>
      </div>
      <div class="item-card" id="card-stickers">
        <span class="icon-keep">✓</span>
        <span>6 stickers/pack</span>
      </div>
    </div>

    
    <div class="column col-ignore">
      <div class="col-header">Extraneous (Ignore!)</div>
      <div class="item-card" id="card-tuesday">
        <span class="icon-ignore">✕</span>
        <span>Tuesday</span>
      </div>
      <div class="item-card" id="card-time">
        <span class="icon-ignore">✕</span>
        <span>3:00 PM</span>
      </div>
    </div>
  </div>

  
  <div class="math-bar">
    <span>Needed for Solution:</span>
    <span class="math-eq">3 × 6 = 18 stickers</span>
  </div>

  <script>
    const chips = document.querySelectorAll('.chip');
    const cards = {
      tuesday: document.getElementById('card-tuesday'),
      time: document.getElementById('card-time'),
      packs: document.getElementById('card-packs'),
      stickers: document.getElementById('card-stickers')
    };

    function clearHighlights() {
      Object.values(cards).forEach(c => c.classList.remove('highlight'));
      chips.forEach(c => c.style.opacity = '1');
    }

    chips.forEach(chip => {
      chip.addEventListener('click', () => {
        const key = chip.getAttribute('data-target');
        clearHighlights();
        cards[key].classList.add('highlight');
      });
    });

    Object.entries(cards).forEach(([key, card]) => {
      card.addEventListener('click', () => {
        clearHighlights();
        card.classList.add('highlight');
        const matchingChip = document.querySelector(`.chip[data-target="${key}"]`);
        if (matchingChip) {
          matchingChip.style.transform = 'scale(1.08)';
          setTimeout(() => {
            matchingChip.style.transform = 'none';
          }, 300);
        }
      });
    });
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <title>Problem-Solving Flow</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      padding: 16px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }
    .flow-container {
      width: 100%;
      max-width: 620px;
      display: flex;
      flex-direction: column;
      gap: 16px;
      align-items: center;
    }
    .steps-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      gap: 8px;
    }
    .step-card {
      flex: 1;
      min-width: 0;
      border-radius: 12px;
      padding: 14px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      border: 2px solid transparent;
      cursor: pointer;
      user-select: none;
      transition: box-shadow 0.25s ease, border-color 0.25s ease;
    }
    .step-card.active {
      box-shadow: 0 0 0 3px rgba(34, 183, 255, 0.45);
    }
    .step-1 {
      background: #e8f5e9;
      border-color: #a5d6a7;
    }
    .step-2 {
      background: #fff8e1;
      border-color: #ffe082;
    }
    .step-3 {
      background: #e3f2fd;
      border-color: #90caf9;
    }
    .icon {
      font-size: 28px;
      line-height: 1;
      margin-bottom: 8px;
    }
    .step-title {
      font-size: 14px;
      font-weight: 700;
      line-height: 1.25;
      margin-bottom: 4px;
      color: #1e2945;
    }
    .step-desc {
      font-size: 12px;
      color: #55607a;
      line-height: 1.2;
    }
    .arrow {
      font-size: 20px;
      font-weight: bold;
      color: #94a3b8;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
    }
    .banner {
      width: 100%;
      background: #fff3e0;
      border: 1px solid #ffcc80;
      border-radius: 8px;
      padding: 10px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #b45309;
      text-align: center;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }
    .controls {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 4px;
    }
    .dot-group {
      display: flex;
      gap: 6px;
    }
    .dot {
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      border: none;
      padding: 0;
      transition: background 0.2s ease, transform 0.2s ease;
    }
    .dot.active {
      background: #22b7ff;
      transform: scale(1.25);
    }
    .btn-step {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      color: #334155;
      border-radius: 6px;
      padding: 4px 10px;
      font-size: 12px;
      font-weight: 600;
      cursor: pointer;
    }
    .btn-step:hover {
      background: #e2e8f0;
    }
    @media (max-width: 480px) {
      .step-card {
        padding: 10px 6px;
      }
      .icon {
        font-size: 22px;
        margin-bottom: 4px;
      }
      .step-title {
        font-size: 12px;
      }
      .step-desc {
        font-size: 11px;
      }
      .arrow {
        font-size: 16px;
      }
      .banner {
        font-size: 12px;
        padding: 8px 10px;
      }
    }
  </style>
</head>
<body>
  <div class="flow-container">
    <div class="steps-row">
      <div class="step-card step-1 active" id="card-0" onclick="setStep(0)">
        <div class="icon">🔍</div>
        <div class="step-title">1. Known Values</div>
        <div class="step-desc">Facts given</div>
      </div>

      <div class="arrow">➔</div>

      <div class="step-card step-2" id="card-1" onclick="setStep(1)">
        <div class="icon">🔑</div>
        <div class="step-title">2. Hidden Question</div>
        <div class="step-desc">The missing bridge</div>
      </div>

      <div class="arrow">➔</div>

      <div class="step-card step-3" id="card-2" onclick="setStep(2)">
        <div class="icon">🏆</div>
        <div class="step-title">3. Target Unknown</div>
        <div class="step-desc">Final answer</div>
      </div>
    </div>

    <div class="banner">
      <span>⚠️</span>
      <span>You cannot reach the Target without solving the Hidden Question first!</span>
    </div>

    <div class="controls">
      <button class="btn-step" onclick="prevStep()">◀ Prev</button>
      <div class="dot-group">
        <button class="dot active" id="dot-0" onclick="setStep(0)" aria-label="Step 1"></button>
        <button class="dot" id="dot-1" onclick="setStep(1)" aria-label="Step 2"></button>
        <button class="dot" id="dot-2" onclick="setStep(2)" aria-label="Step 3"></button>
      </div>
      <button class="btn-step" onclick="nextStep()">Next ▶</button>
    </div>
  </div>

  <script>
    let currentStep = 0;
    const totalSteps = 3;

    function setStep(index) {
      currentStep = index;
      for (let i = 0; i < totalSteps; i++) {
        const card = document.getElementById(`card-${i}`);
        const dot = document.getElementById(`dot-${i}`);
        if (i === currentStep) {
          card.classList.add('active');
          dot.classList.add('active');
        } else {
          card.classList.remove('active');
          dot.classList.remove('active');
        }
      }
    }

    function nextStep() {
      setStep((currentStep + 1) % totalSteps);
    }

    function prevStep() {
      setStep((currentStep - 1 + totalSteps) % totalSteps);
    }
  </script>
</body>
</html>

Recognizing Attributes of Flat Shapes

Sorting Flat Shapes by Sides and Angles

Recognizing Attributes of Solid Figures

Sorting Solid Figures by Faces, Edges, and Vertices

Classifying Cones, Cylinders, and Spheres

Classifying Prisms and Cubes

Using Formal Geometric Vocabulary

math

Classifying 2D and 3D Figures

Understanding Place Value Relationships in Multi-Digit Numbers

Introducing the Ten-Thousands Place

Introducing the Hundred-Thousands Place

Building Numbers to 100,000 with Base-Ten Models

Reading and Writing Numbers Up to 100,000

Writing Expanded Form to 100,000

Breaking Apart Numbers to 100,000

Using Place Value Charts to 100,000

Naming the Value of Each Digit to Hundred-Thousands

Composing Numbers from Expanded Form to 100,000

Composing and Decomposing Numbers to 100,000

Naming Place Value Positions to Hundred Thousands

Reading and Writing Numbers to 100,000

Finding the Value of a Digit in Six-Digit Numbers

Ten Times the Value: Place Value Relationships

Shifting Digits and Place Value Patterns

Describing Place Value Relationships With Words

Exploring Place Value to Hundred Thousands

Identifying Extra and Missing Information in Word Problems

Formulating a Multi-Step Plan for Word Problems

Choosing Between Computational and Visual Math Tools

Using Bar Models and Tape Diagrams to Solve Problems

Justifying Mathematical Solutions with Precise Language

Evaluating Reasonableness and Practical Constraints

Finding and Correcting Errors in Mathematical Arguments

Mathematical Problem Solving and Strategic Reasoning

Understanding Multiplication as 'Times As Much'

Solving 'Times As Much' Comparison Word Problems

Finding the Missing Factor in Multiplication Equations

Finding the Missing Product in Multiplication Equations

Finding the Unknown in Division Equations

Representing Multiplication Problems with Arrays and Equations

Multiplicative Comparison and Unknown Numbers

Connecting Repeated Addition to Equal Groups

Modeling Arrays Up to 10 by 10

Using Number Lines to Show Multiplication

Area Models for Multiplication Facts

Skip Counting to Find Products

Drawing Arrays to Match Multiplication Sentences

Writing Multiplication Equations from Equal Groups

Finding the Total in Arrays Up to 10 by 10

Comparing Multiplication Representations

Understanding Multiplication Concepts

What Is a Fraction? Parts of a Whole

Numerator and Denominator: What They Mean

Understanding Unit Fractions as One Part of a Whole

Partitioning Shapes into Thirds and Sixths

Fractions with Denominators 2, 3, 4, 6, and 8

Representing Fractions with Strip Diagrams

Identifying Fractions from Area Models

Understanding Unit Fractions and Fraction Models

认识24时计时法与钟面对应

普通计时法与24时计时法的互换

计算跨昼夜的经过时间

大月小月与平年闰年的规律

制作年历与季度天数统计

中国古代土圭之法与二十四节气

四季变化与地球公转周期探究

年月日的秘密与历法探秘

Multiplying by 0 and 1: Zero and Identity Properties

Multiplying by 2: Connecting to Doubles

Multiplying by 3: Using Known Facts

Multiplying by 4: Double-Double Strategy

Multiplying by 5 Using Skip-Counting

Multiplying by 6: Patterns and Strategies

Multiplying by 7: Patterns and Strategies

Multiplying by 8: Patterns and Strategies

Multiplying by 9: Patterns and Strategies

Multiplying by 10 Using Place Value

Building Multiplication Fact Fluency: Factors 0–10

Placing Fractions on a Number Line

Labeling Fractions on a Number Line

Finding Fractions at Points on a Number Line

Whole Numbers as Fractions on a Number Line

Placing Fractions Greater Than One on a Number Line

Fractions Greater Than One with Area Models

Matching Area Models to Number Lines

Fractions on Number Lines

Strip Diagrams for Two-Step Addition and Subtraction Problems

Strip Diagrams for Two-Step Multiplication and Division Problems

Matching Strip Diagrams to Equations

Justifying and Evaluating Solutions to Multi-Step Word Problems

Modeling Two-Step Problems with Diagrams and Equations

How Digits Shift Across Place Values to 100,000

Describing Place Value Relationships Through Hundred-Thousands

Locating Numbers on Number Lines to 100,000

Rounding to the Nearest Ten Using Number Lines

Rounding to the Nearest Hundred Using Number Lines

Rounding to the Nearest Thousand Using Number Lines

Rounding to the Nearest Ten-Thousand Using Number Lines

Using Words to Describe Relative Size for Rounding

Rounding to Different Place Values: Mixed Practice

Place Value Patterns and Rounding to 100,000

What Makes a Quadrilateral?

Recognizing Rectangles and Squares as Quadrilaterals

Recognizing Parallelograms as Quadrilaterals

Recognizing Rhombuses as Quadrilaterals

Recognizing Trapezoids as Quadrilaterals

Quadrilaterals Outside Known Subcategories

Drawing Shapes With Given Attributes

Classifying Quadrilaterals in Real-Life Objects

Understanding Quadrilaterals

认识质量单位克与千克

认识大型质量单位吨

克、千克、吨之间的单位换算与比较

曹冲称象中的等量替换原理

设计测量超大超重物体的实践方案

曹冲称象与质量度量衡

Area of a Rectangle Using Unit Squares

Tiling Rectangles to Find Area

Connecting Rows to Multiplication for Area

Multiplying Side Lengths to Find Area

Area Word Problems With Rectangles

Using the Distributive Property for Area

Area of Rectangles With Multiplication

Comparing Five-Digit Numbers With Symbols

Comparing Six-Digit Numbers With Symbols

Ordering Numbers From Least to Greatest to 100,000

Ordering Numbers From Greatest to Least to 100,000

Comparing and Ordering Numbers to 100,000

Comparing Numbers to 100,000

Ordering Numbers to 100,000

Using >, <, and = Symbols with Numbers to 100,000

Place Value Word Problems to 100,000

Choosing Tools for Place Value Problems

Patterns in Place Value to 100,000

Reading Number Lines with Different Scales

Comparing and Ordering on Number Lines to 100,000

Place Value in the Real World

Comparing, Ordering, and Applying Numbers to 100,000

Composing Fractions from Unit Fractions

Decomposing Fractions into Unit Fractions

Writing Fractions as Sums of Unit Fractions

Fractions of a Set of Objects

Sharing Objects Equally Among Recipients

Solving Fraction Sharing Problems with Pictorial Models

Composing, Decomposing, and Fractions of a Set

Multiplying by 11 and 12: Extending Fact Fluency

Mixed Multiplication Facts Practice (0–10)

Multiplication Facts Speed Practice

Using Multiplication Facts to Solve Problems

Extending and Applying Multiplication Fact Fluency

Input-Output Tables: Finding the Rule

Representing Real-World Relationships in Tables

Arithmetic Patterns in Addition and Multiplication

Properties of Operations: Commutative and Associative

Balancing Equations with Multiplication and Division

Patterns, Tables, and Properties of Operations

Rzuty dziesiątek i setek

Zaokrąglanie liczb do dziesiątek

Zaokrąglanie liczb do setek i tysięcy

Szacowanie liczb w kontekście

Liczby w otoczeniu – odczytywanie i porządkowanie

Zagadki cyfrowe – logiczne zadania z liczbami

Sprawdzenie – liczby i ich własności

Rachunki pamięciowe, zaokrąglanie i zastosowania

认识东南西北与平面图定向

认识东北、西北、东南、西南四个方向

描绘物体相对位置与方向相对性

了解“几点钟方向”的描述方法

设计与解读寻宝路线图

寻宝大冒险与空间方位

Breaking Apart Composite Figures

Finding Area of Composite Rectangles

Area of L-Shaped Figures

Area of Composite Figures Word Problems

Partitioning Shapes Into Equal Areas

Expressing Area as Unit Fractions

Same Whole, Different-Shaped Equal Shares

Equal Shares in the Real World

Composite Figures and Equal Shares

Using the Commutative Property to Multiply

Using the Associative Property to Multiply

Distributive Property with Area Models

Breaking Apart Numbers Using the Distributive Property

Multiplying by Multiples of Ten

Multiplication Properties and Place Value Patterns

Rounding to the Nearest Thousand

Rounding to the Nearest Ten Thousand

Rounding Word Problems and Estimation

Rounding Whole Numbers

Using Place Value to Add Three-Digit Numbers

Using Place Value to Subtract Three-Digit Numbers

Adding Three-Digit Numbers Without Regrouping

Subtracting Three-Digit Numbers Without Regrouping

Three-Digit Addition and Subtraction Strategies

OGM.4.PR.1

Aligned learning resources

Related diagrams