<!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>Area Model: 235 × 46</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-tap-highlight-color: transparent;
      user-select: none;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    .header {
      text-align: center;
      margin-bottom: 6px;
    }

    .title {
      font-size: 18px;
      font-weight: 700;
      color: #0f172a;
      letter-spacing: -0.01em;
    }

    /* Stepper Controls */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      margin-bottom: 8px;
      flex-wrap: wrap;
    }

    .btn-step {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 20px;
      padding: 4px 10px;
      font-size: 12px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
    }

    .btn-step.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
    }

    .btn-play {
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      border-radius: 50%;
      width: 26px;
      height: 26px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 11px;
      cursor: pointer;
      color: #334155;
    }

    /* Diagram Area */
    .model-wrapper {
      width: 100%;
      max-width: 480px;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }

    /* Main Grid Structure */
    .grid-container {
      display: grid;
      grid-template-columns: 36px 4.5fr 2.6fr 1.5fr 68px;
      gap: 4px;
      align-items: stretch;
    }

    /* Header Labels */
    .corner-blank {
      grid-column: 1;
      grid-row: 1;
    }

    .top-label {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      padding: 4px 0;
      text-align: center;
      font-size: 13px;
      font-weight: 700;
      color: #0369a1;
      transition: background 0.3s ease, border-color 0.3s ease;
    }

    .row-sum-head {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
      display: flex;
      align-items: center;
      justify-content: center;
      text-transform: uppercase;
      letter-spacing: 0.03em;
    }

    .side-label {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 700;
      color: #b45309;
      transition: background 0.3s ease, border-color 0.3s ease;
    }

    /* Cells */
    .cell {
      border-radius: 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 6px 2px;
      border: 1.5px solid transparent;
      cursor: pointer;
      transition: transform 0.2s ease, opacity 0.3s ease, box-shadow 0.2s ease, border-color 0.2s ease;
      position: relative;
    }

    .cell-calc {
      font-size: 11px;
      font-weight: 500;
      color: #475569;
      margin-bottom: 2px;
      white-space: nowrap;
    }

    .cell-prod {
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
      white-space: nowrap;
    }

    /* Row 1 cells */
    .r1-c1 { background: #e0f2fe; border-color: #bae6fd; min-height: 52px; }
    .r1-c2 { background: #ede9fe; border-color: #ddd6fe; }
    .r1-c3 { background: #fce7f3; border-color: #fbcfe8; }

    /* Row 2 cells */
    .r2-c1 { background: #bae6fd; border-color: #7dd3fc; min-height: 44px; }
    .r2-c2 { background: #ddd6fe; border-color: #c4b5fd; }
    .r2-c3 { background: #fbcfe8; border-color: #f472b6; }

    /* Row Totals */
    .row-total {
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 700;
      color: #0f172a;
      transition: background 0.3s ease, border-color 0.3s ease, transform 0.2s ease;
    }

    .row-total span {
      font-size: 9px;
      font-weight: 600;
      color: #64748b;
      margin-top: 1px;
    }

    /* Highlight States */
    .dimmed {
      opacity: 0.3;
    }

    .highlight-active {
      box-shadow: 0 0 0 2px #0284c7;
      border-color: #0284c7 !important;
    }

    .highlight-label {
      background: #0284c7 !important;
      color: #ffffff !important;
      border-color: #0284c7 !important;
    }

    .highlight-total {
      background: #e0f2fe !important;
      border-color: #0284c7 !important;
      color: #0369a1 !important;
    }

    /* Final Sum Box */
    .final-sum-bar {
      margin-top: 6px;
      background: #f8fafc;
      border: 1.5px dashed #cbd5e1;
      border-radius: 8px;
      padding: 8px 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
    }

    .final-sum-bar.highlight-final {
      background: #ecfdf5;
      border: 1.5px solid #10b981;
      box-shadow: 0 2px 6px rgba(16, 185, 129, 0.15);
    }

    .num-part {
      padding: 2px 6px;
      border-radius: 4px;
      transition: background 0.2s ease;
    }

    .p1 { background: #e0f2fe; color: #0369a1; }
    .p2 { background: #fce7f3; color: #9d174d; }
    .p-total { background: #10b981; color: #ffffff; padding: 3px 8px; border-radius: 6px; font-size: 15px; }

    @media (max-width: 380px) {
      .title { font-size: 16px; }
      .grid-container { grid-template-columns: 30px 4.2fr 2.6fr 1.6fr 58px; gap: 3px; }
      .top-label, .side-label { font-size: 11px; }
      .cell-calc { font-size: 9px; }
      .cell-prod { font-size: 12px; }
      .row-total { font-size: 11px; }
      .final-sum-bar { font-size: 12px; padding: 6px 8px; gap: 4px; }
      .p-total { font-size: 13px; }
    }
  </style>
</head>
<body>

  <div class="header">
    <div class="title">235 × 46 = 10,810</div>
  </div>

  <div class="controls">
    <button class="btn-play" id="playBtn" title="Auto Play">▶</button>
    <button class="btn-step active" data-step="0">All</button>
    <button class="btn-step" data-step="1">Row 40</button>
    <button class="btn-step" data-step="2">Row 6</button>
    <button class="btn-step" data-step="3">Total</button>
  </div>

  <div class="model-wrapper">
    <div class="grid-container">
      
      <div class="corner-blank"></div>
      <div class="top-label col-1" id="lbl-200">200</div>
      <div class="top-label col-2" id="lbl-30">30</div>
      <div class="top-label col-3" id="lbl-5">5</div>
      <div class="row-sum-head">Total</div>

      
      <div class="side-label row-1" id="lbl-40">40</div>
      <div class="cell r1-c1 row-1 col-1" data-r="1" data-c="1">
        <span class="cell-calc">200 × 40</span>
        <span class="cell-prod">8,000</span>
      </div>
      <div class="cell r1-c2 row-1 col-2" data-r="1" data-c="2">
        <span class="cell-calc">30 × 40</span>
        <span class="cell-prod">1,200</span>
      </div>
      <div class="cell r1-c3 row-1 col-3" data-r="1" data-c="3">
        <span class="cell-calc">5 × 40</span>
        <span class="cell-prod">200</span>
      </div>
      <div class="row-total row-1" id="sum-r1">
        9,400
        <span>Row 1</span>
      </div>

      
      <div class="side-label row-2" id="lbl-6">6</div>
      <div class="cell r2-c1 row-2 col-1" data-r="2" data-c="1">
        <span class="cell-calc">200 × 6</span>
        <span class="cell-prod">1,200</span>
      </div>
      <div class="cell r2-c2 row-2 col-2" data-r="2" data-c="2">
        <span class="cell-calc">30 × 6</span>
        <span class="cell-prod">180</span>
      </div>
      <div class="cell r2-c3 row-2 col-3" data-r="2" data-c="3">
        <span class="cell-calc">5 × 6</span>
        <span class="cell-prod">30</span>
      </div>
      <div class="row-total row-2" id="sum-r2">
        1,410
        <span>Row 2</span>
      </div>
    </div>

    
    <div class="final-sum-bar" id="finalBar">
      <span class="num-part p1">9,400</span>
      <span>+</span>
      <span class="num-part p2">1,410</span>
      <span>=</span>
      <span class="p-total">10,810</span>
    </div>
  </div>

  <script>
    const steps = [
      { id: 0, desc: 'All' },
      { id: 1, desc: 'Row 40' },
      { id: 2, desc: 'Row 6' },
      { id: 3, desc: 'Total' }
    ];

    let currentStep = 0;
    let autoPlayTimer = null;

    const stepBtns = document.querySelectorAll('.btn-step');
    const playBtn = document.getElementById('playBtn');
    const cells = document.querySelectorAll('.cell');
    const row1Elems = document.querySelectorAll('.row-1');
    const row2Elems = document.querySelectorAll('.row-2');
    const allCells = document.querySelectorAll('.cell, .side-label, .top-label, .row-total');
    const finalBar = document.getElementById('finalBar');

    const lbl40 = document.getElementById('lbl-40');
    const lbl6 = document.getElementById('lbl-6');
    const sumR1 = document.getElementById('sum-r1');
    const sumR2 = document.getElementById('sum-r2');

    function applyStep(stepIndex) {
      currentStep = stepIndex;

      // Update button styles
      stepBtns.forEach(btn => {
        btn.classList.toggle('active', parseInt(btn.dataset.step, 10) === stepIndex);
      });

      // Clear all transient highlights
      allCells.forEach(el => {
        el.classList.remove('dimmed', 'highlight-active', 'highlight-label', 'highlight-total');
      });
      finalBar.classList.remove('highlight-final');

      if (stepIndex === 0) {
        // Show everything clearly
        return;
      }

      if (stepIndex === 1) {
        // Highlight Row 1 (x40)
        row2Elems.forEach(el => el.classList.add('dimmed'));
        lbl40.classList.add('highlight-label');
        sumR1.classList.add('highlight-total');
        document.querySelectorAll('.cell.row-1').forEach(c => c.classList.add('highlight-active'));
      } else if (stepIndex === 2) {
        // Highlight Row 2 (x6)
        row1Elems.forEach(el => el.classList.add('dimmed'));
        lbl6.classList.add('highlight-label');
        sumR2.classList.add('highlight-total');
        document.querySelectorAll('.cell.row-2').forEach(c => c.classList.add('highlight-active'));
      } else if (stepIndex === 3) {
        // Highlight Row sums + Total bar
        document.querySelectorAll('.cell').forEach(c => c.classList.add('dimmed'));
        sumR1.classList.add('highlight-total');
        sumR2.classList.add('highlight-total');
        finalBar.classList.add('highlight-final');
      }
    }

    // Step button click handlers
    stepBtns.forEach(btn => {
      btn.addEventListener('click', () => {
        stopAutoPlay();
        applyStep(parseInt(btn.dataset.step, 10));
      });
    });

    // Cell direct interactive click: focus on factors
    cells.forEach(cell => {
      cell.addEventListener('click', () => {
        stopAutoPlay();
        const r = cell.dataset.r;
        const c = cell.dataset.c;

        allCells.forEach(el => el.classList.add('dimmed'));
        finalBar.classList.remove('highlight-final');

        cell.classList.remove('dimmed');
        cell.classList.add('highlight-active');

        // Highlight corresponding row & col labels
        if (r === '1') lbl40.classList.remove('dimmed'), lbl40.classList.add('highlight-label');
        if (r === '2') lbl6.classList.remove('dimmed'), lbl6.classList.add('highlight-label');

        if (c === '1') document.getElementById('lbl-200').classList.remove('dimmed'), document.getElementById('lbl-200').classList.add('highlight-label');
        if (c === '2') document.getElementById('lbl-30').classList.remove('dimmed'), document.getElementById('lbl-30').classList.add('highlight-label');
        if (c === '3') document.getElementById('lbl-5').classList.remove('dimmed'), document.getElementById('lbl-5').classList.add('highlight-label');
      });
    });

    // Auto-play Stepper
    function startAutoPlay() {
      playBtn.textContent = '⏸';
      autoPlayTimer = setInterval(() => {
        const next = (currentStep + 1) % steps.length;
        applyStep(next);
      }, 3200);
    }

    function stopAutoPlay() {
      if (autoPlayTimer) {
        clearInterval(autoPlayTimer);
        autoPlayTimer = null;
        playBtn.textContent = '▶';
      }
    }

    playBtn.addEventListener('click', () => {
      if (autoPlayTimer) {
        stopAutoPlay();
      } else {
        startAutoPlay();
      }
    });

    // Initialize
    applyStep(0);
  </script>
</body>
</html>

Multiplying Multi-Digit Numbers Using Area and Array Models

<!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: #ffffff;
      padding: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    .main-container {
      width: 100%;
      max-width: 620px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    /* Equation header */
    .title-row {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 8px;
      font-size: 17px;
      font-weight: 700;
    }
    .badge-top {
      background: #e0f2fe;
      color: #0369a1;
      padding: 2px 8px;
      border-radius: 6px;
    }
    .badge-left {
      background: #fef3c7;
      color: #b45309;
      padding: 2px 8px;
      border-radius: 6px;
    }

    /* Area Model Grid */
    .grid-wrapper {
      display: grid;
      grid-template-columns: 46px 2.2fr 1.1fr 1fr 0.8fr 1.6fr;
      gap: 4px;
      align-items: stretch;
      font-size: 13px;
    }

    .header-cell {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      padding: 4px 2px;
      border-radius: 6px;
    }
    .col-header {
      background: #f0f9ff;
      color: #0284c7;
      border: 1px solid #bae6fd;
    }
    .row-header {
      background: #fffbeb;
      color: #d97706;
      border: 1px solid #fde68a;
    }
    .corner-cell {
      background: #f8fafc;
      color: #94a3b8;
      font-size: 16px;
    }
    .sum-header {
      background: #f1f5f9;
      color: #475569;
      border: 1px dashed #cbd5e1;
      font-size: 12px;
    }

    .cell {
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 6px 2px;
      cursor: pointer;
      transition: background-color 0.2s, border-color 0.2s, box-shadow 0.2s;
    }
    .cell:hover, .cell.active {
      background: #eff6ff;
      border-color: #3b82f6;
      box-shadow: inset 0 0 0 1px #3b82f6;
    }
    .cell-calc {
      font-size: 11px;
      color: #64748b;
      margin-bottom: 2px;
    }
    .cell-val {
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
    }

    .row-sum {
      background: #fafaf9;
      border: 1px solid #e7e5e4;
      border-radius: 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 4px;
      font-weight: 700;
      font-size: 13px;
      color: #334155;
    }

    /* Grand Total Bar */
    .total-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f0fdf4;
      border: 1.5px solid #86efac;
      border-radius: 8px;
      padding: 8px 14px;
      font-size: 14px;
      font-weight: 600;
      color: #166534;
      flex-wrap: wrap;
      gap: 6px;
    }
    .grand-total {
      font-size: 18px;
      font-weight: 800;
      color: #15803d;
    }

    /* Stepper Controls */
    .controls {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 8px;
    }
    .btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #334155;
      font-size: 13px;
      font-weight: 600;
      padding: 5px 12px;
      border-radius: 6px;
      cursor: pointer;
    }
    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }

    @media (max-width: 480px) {
      .grid-wrapper {
        font-size: 11px;
      }
      .cell-calc {
        font-size: 9px;
      }
      .cell-val {
        font-size: 11px;
      }
      .row-sum {
        font-size: 11px;
      }
      .total-bar {
        font-size: 12px;
        justify-content: center;
      }
      .grand-total {
        font-size: 15px;
      }
    }
  </style>
</head>
<body>
  <div class="main-container">
    <div class="title-row">
      <span class="badge-top">3,142</span>
      <span>×</span>
      <span class="badge-left">25</span>
      <span>=</span>
      <span style="color: #15803d; font-size: 19px;">78,550</span>
    </div>

    
    <div class="grid-wrapper">
      
      <div class="header-cell corner-cell">×</div>
      <div class="header-cell col-header">3,000</div>
      <div class="header-cell col-header">100</div>
      <div class="header-cell col-header">40</div>
      <div class="header-cell col-header">2</div>
      <div class="header-cell sum-header">Row Sum</div>

      
      <div class="header-cell row-header">20</div>
      <div class="cell" data-idx="0">
        <span class="cell-calc">20 × 3000</span>
        <span class="cell-val">60,000</span>
      </div>
      <div class="cell" data-idx="1">
        <span class="cell-calc">20 × 100</span>
        <span class="cell-val">2,000</span>
      </div>
      <div class="cell" data-idx="2">
        <span class="cell-calc">20 × 40</span>
        <span class="cell-val">800</span>
      </div>
      <div class="cell" data-idx="3">
        <span class="cell-calc">20 × 2</span>
        <span class="cell-val">40</span>
      </div>
      <div class="row-sum" id="row-sum-1">
        <span style="font-size:10px; color:#64748b;">(20 × 3,142)</span>
        <span>62,840</span>
      </div>

      
      <div class="header-cell row-header">5</div>
      <div class="cell" data-idx="4">
        <span class="cell-calc">5 × 3000</span>
        <span class="cell-val">15,000</span>
      </div>
      <div class="cell" data-idx="5">
        <span class="cell-calc">5 × 100</span>
        <span class="cell-val">500</span>
      </div>
      <div class="cell" data-idx="6">
        <span class="cell-calc">5 × 40</span>
        <span class="cell-val">200</span>
      </div>
      <div class="cell" data-idx="7">
        <span class="cell-calc">5 × 2</span>
        <span class="cell-val">10</span>
      </div>
      <div class="row-sum" id="row-sum-2">
        <span style="font-size:10px; color:#64748b;">(5 × 3,142)</span>
        <span>15,710</span>
      </div>
    </div>

    
    <div class="total-bar">
      <span>Total: 62,840 + 15,710</span>
      <span class="grand-total">= 78,550</span>
    </div>

    
    <div class="controls">
      <button class="btn active" id="btn-all" onclick="setMode('all')">Show All</button>
      <button class="btn" id="btn-row1" onclick="setMode('row1')">Row 20</button>
      <button class="btn" id="btn-row2" onclick="setMode('row2')">Row 5</button>
    </div>
  </div>

  <script>
    const cells = document.querySelectorAll('.cell');
    const r1 = document.getElementById('row-sum-1');
    const r2 = document.getElementById('row-sum-2');
    const btnAll = document.getElementById('btn-all');
    const btnRow1 = document.getElementById('btn-row1');
    const btnRow2 = document.getElementById('btn-row2');

    function setMode(mode) {
      btnAll.classList.remove('active');
      btnRow1.classList.remove('active');
      btnRow2.classList.remove('active');

      cells.forEach((cell, i) => {
        if (mode === 'all') {
          cell.style.opacity = '1';
          cell.classList.remove('active');
        } else if (mode === 'row1') {
          cell.style.opacity = i < 4 ? '1' : '0.25';
          cell.classList.toggle('active', i < 4);
        } else if (mode === 'row2') {
          cell.style.opacity = i >= 4 ? '1' : '0.25';
          cell.classList.toggle('active', i >= 4);
        }
      });

      if (mode === 'all') {
        btnAll.classList.add('active');
        r1.style.opacity = '1';
        r2.style.opacity = '1';
      } else if (mode === 'row1') {
        btnRow1.classList.add('active');
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        <div class="dim-label dim-top">8</div>

        
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          <span>2,400</span>
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Reviewing 2-Digit × 2-Digit Multiplication

Multiplying 2-Digit × 3-Digit with Partial Products

Multiplying 2-Digit × 3-Digit with the Standard Algorithm

Multiplying 2-Digit × 4-Digit Numbers

Multiplying When Factors Contain Zeros

Estimating Products with Compatible Numbers

math

Multi-Digit Multiplication: Computing with Larger Factors

Multiplication Word Problems with Large Numbers

Multi-Step Multiplication Word Problems

Balancing Multiplication Equations with Large Numbers

Multiplication Inequalities with Large Numbers

Choosing Strategies for Multi-Digit Multiplication

Using a Problem-Solving Model for Multiplication and Division

Multiplication Fluency: 3-Digit × 2-Digit

Multi-Digit Multiplication: Applications and Fluency

Review: Multiplying 2-Digit by 1-Digit Numbers

Review: Multiplying 3-Digit by 1-Digit Numbers

Connecting Partial Products to the Standard Algorithm

Multiplying 2-Digit by 2-Digit: Standard Algorithm

Multiplying 3-Digit by 2-Digit: Partial Products

Multiplying 3-Digit by 2-Digit: Standard Algorithm

Multiplying with Zeros in Factors

Multi-Digit Multiplication: Building to 3-Digit by 2-Digit

Multiplying Four-Digit Numbers by One-Digit Numbers

Multiplying Two-Digit Numbers by Two-Digit Numbers Fluently

Multiplying Three-Digit Numbers by Two-Digit Numbers

Multiplying Four-Digit Numbers by Two-Digit Numbers

Mental Multiplication Using Distributive and Associative Properties

Multi-Digit Multiplication Word Problems and Applications

Multi-Digit Multiplication Strategies and Algorithms

Multiplication Patterns Across Place Values

Using Properties to Multiply Mentally

Multiplying Three Factors Together

Area Models for 3-Digit by 2-Digit Multiplication

Multiplication Properties, Patterns, and Models

Balancing Multiplication Equations

Multiplication Inequalities

Two-Step Multiplication Word Problems

Choosing Multiplication Strategies

Multiplication Error Analysis

Applying Multiplication: Equations, Problems, and Error Analysis

Multiplying Multiples of 10 and 100 Mentally

Multiplying Three-Digit by One-Digit Numbers Using Partial Products

Formal Written Algorithm for Multiplication by One-Digit Numbers

Multiplying Two-Digit by Two-Digit Numbers Using Area Models

Formal Written Algorithm for Two-Digit Multiplication

Multiplying Three-Digit by Two-Digit Numbers

Choosing Between Mental and Written Multiplication Methods

Using Digital Calculators to Verify and Investigate Multiplication

Estimating and Checking the Reasonableness of Multiplication Products

Solving Real-World Multi-Digit Multiplication Word Problems

Multi-Digit Multiplication Strategies

Multiplying 2-Digit by 1-Digit: Partial Products

Multiplying 3-Digit by 1-Digit: Standard Algorithm

Multiplying 4-Digit by 1-Digit: Standard Algorithm

Multiplying Large Numbers by Single-Digit Numbers

Multiplying by Multiples of 10

Multiplying by Single-Digit Numbers

Identifying Multiples and Common Multiples

Finding Lowest Common Multiples in Context

Understanding Factors Using Arrays and Area Models

Finding All Factor Pairs of a Number Systematically

Finding Common Factors of Two Numbers

Finding the Highest Common Factor of Two Numbers

Sorting Numbers by Multiples and Factors Using Venn Diagrams

Divisibility Rules for 2, 3, 4, 5, 6, 9, and 10

Solving Word Problems Involving Factors and Multiples

Multiples, Factors, and Common Factors

Multiplying 2-Digit by 2-Digit: Area Model

Multiplying 2-Digit by 2-Digit: Partial Products

Multiplying Large Numbers by Two-Digit Numbers

Multiplying 4-Digit by 2-Digit: Standard Algorithm

Multiplying Large Numbers by Three-Digit Numbers

Multiplying by Two-Digit and Three-Digit Numbers

Szacowanie pierwiastków kwadratowych

Szacowanie pierwiastków sześciennych

Szacowanie wyrażeń arytmetycznych z pierwiastkami

Między jakimi liczbami całkowitymi leży pierwiastek

Porównywanie pierwiastka z liczbą wymierną

Znajdowanie liczb wymiernych blisko pierwiastka

Szacowanie i porównywanie pierwiastków

Multiplying With Zeros in the Factors

Estimating Products by Rounding

Multiplication Word Problems

Finding Missing Factors in Multiplication Equ

Multiplication Fluency Practice

Multi-Digit Multiplication Applications and Fluency

Pierwiastek z iloczynu dwóch liczb

Pierwiastek z ilorazu dwóch liczb

Wyłączanie liczby przed znak pierwiastka

Włączanie liczby pod znak pierwiastka

Wyłączanie i włączanie – zadania

Mnożenie pierwiastków tego samego stopnia

Dzielenie pierwiastków tego samego stopnia

Mnożenie i dzielenie pierwiastków – zadania

Pierwiastki – działania łączne

Porównywanie wyrażeń z pierwiastkami

Przekształcanie wyrażeń z pierwiastkami

Understanding Square Numbers with Grid and Tile Models

Recalling and Calculating Square Numbers up to 12²

Calculating Squares of Multiples of 10

Understanding Cube Numbers with Multilink Cubes

Calculating and Recalling Cube Numbers from 1³ to 5³

Calculating Cubes of Larger Numbers up to 10³

Evaluating Expressions with Square and Cube Numbers

Solving Word Problems and Puzzles Involving Squares and Cubes

Square Numbers and Cube Numbers

Twierdzenie Pitagorasa – wprowadzenie

Twierdzenie Pitagorasa – obliczanie przeciwprostokątnej

Twierdzenie Pitagorasa – obliczanie przyprostokątnej

Twierdzenie Pitagorasa – zadania praktyczne

Pierwiastki – zadania mieszane

Sprawdzenie umiejętności – pierwiastki

Twierdzenie Pitagorasa i utrwalenie pierwiastków

Multiplying Multiples of 10 and 100 Using Known Facts

Dividing Multiples of 10 and 100 Using Place Value Facts

Mental Multiplication Using Doubling and Halving

Multiplying by 4, 8, 16, and 32 by Repeated Doubling

Dividing by 4 and 8 by Repeated Halving

Multiplying by 19, 29, and Near-Multiples Using Compensation

Multiplying by 5, 25, and 50 Using Powers of 10 and Halving

Using the Distributive Law for Mental Multiplication

Multiplying Three Numbers Mentally Using Associativity

Mental Multiplication and Division

Short Multiplication: 2- and 3-Digit Numbers by 1-Digit

Short Multiplication: 4-Digit Numbers by 1-Digit

Multiplying Numbers with Zeros Using Short Multiplication

Transitioning from Grid Method to Long Multiplication

Long Multiplication: 2-Digit Numbers by 2-Digit Numbers

Long Multiplication: 3-Digit Numbers by 2-Digit Numbers

Long Multiplication: 4-Digit Numbers by 2-Digit Numbers

Estimating and Checking Long Multiplication Calculations

Finding Missing Digits in Short and Long Multiplication

Solving Multi-Step Word Problems with Multiplication

Formal Written Multiplication

Making Line Plots With Fractional Measurements

Interpreting Line Plots With Fractions

Introduction to Volume: Counting Unit Cubes

Finding Volume Using Multiplication

Classifying Two-Dimensional Figures by Properties

Understanding Hierarchies of Shapes

Line Plots, Volume, and Geometry

What Is Volume? Understanding Solid Figures

The Unit Cube and Cubic Units

Packing With Unit Cubes: No Gaps or Overlaps

Counting Unit Cubes to Find Volume

Introduction to Volume with Unit Cubes

Prawdopodobieństwo zdarzeń – wprowadzenie

Prawdopodobieństwo zdarzeń złożonych

Statystyka – średnia arytmetyczna i mediana

Odczytywanie i interpretacja danych z wykresów

Zadania mieszane – powtórzenie całego materiału

Sprawdzenie końcowe – zadania z całego materiału

Statystyka, prawdopodobieństwo i powtórzenie końcowe

Relating Volume to Multiplication

Packing Prisms With Cubes, Then Multiplying

Volume Formula: Length × Width × Height

Volume Formula: Base × Height

The Associative Property and Volume

Volume of Prisms With Different Orientations

Finding Missing Dimensions Given the Volume

Volume of Rectangular Prisms

OGM.6.NBT.6

OGM.6.NBT.6

Aligned learning resources

Related diagrams