Advanced

Tutor model

i62 💰:9.4

i52 💰:7.9

🏆 i67 💰:62.5

i70 💰:125.0

i68 💰:125.0

🏆 i66 💰:75.0

i65 💰:125.0

i63 💰:62.5

i61 💰:75.0

i60 💰:9.4

i60 💰:37.5

i58 💰:62.5

i57 💰:22.5

i57 💰:37.5

i56 💰:45.0

⚡ i55 💰:11.25

i55 💰:37.5

i54 💰:62.5

i52 💰:35.0

i51 💰:37.5

i49 💰:15.0

i49 💰:62.5

i48 💰:11.3

i47 💰:7.5

i44 💰:25.0

i43 💰:37.5

i42 💰:187.5

i40 💰:5.0

i39 💰:100.0

i38 💰:37.5

i37 💰:11.0

i36 💰:187.5

i34 💰:12.5

i33 💰:37.5

i30 💰:1.0

i29 💰:1.5

i28 💰:150.0

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i20 💰:4.0

i18 💰:1.0

i16 💰:25.0

i13 💰:1.5

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What would you like to learn?

Override for the tutor's lesson content generation calls. Auto uses the system default (Claude Sonnet 5 for lesson text, Opus 5 for diagrams).

Lesson generation model

System default

i58 💰:18.8

i31 💰:11.0

i25 💰:31.3

Tutoring abilities

Imagine reading a full page about deep-sea creatures, but when your friend asks what you just read, your mind goes completely blank!

**Informational text** gives you real-world facts about science, history, and nature, but you do not have to memorize every single word to master it.

How do expert readers instantly spot what matters most in a complex passage?

The **topic** is simply the broad subject of the text in just one or two words, like *volcanoes* or *honeybees*.

The **main idea** is the specific central point or big message that the author wants you to learn about that topic.

<!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>Main Idea and Supporting Details Structure</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #f8f9fa;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 16px;
      user-select: none;
      -webkit-user-select: none;
    }

    /* Controls */
    .nav-tabs {
      display: flex;
      gap: 8px;
      flex-wrap: wrap;
      justify-content: center;
      width: 100%;
      max-width: 420px;
      margin-bottom: 12px;
    }

    .tab-btn {
      flex: 1 1 calc(25% - 8px);
      min-width: 70px;
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      color: #64748b;
      padding: 8px 10px;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
    }

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

    /* Structure stage */
    .stage {
      position: relative;
      width: 100%;
      max-width: 380px;
      height: 280px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 12px 0;
    }

    /* Roof / Main Idea */
    .main-idea-block {
      width: 90%;
      height: 64px;
      background: #0284c7;
      color: #ffffff;
      border-radius: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 17px;
      box-shadow: 0 4px 12px rgba(2, 132, 199, 0.2);
      transition: transform 0.3s ease, opacity 0.3s ease, box-shadow 0.3s ease;
      z-index: 2;
    }

    .main-idea-block.highlight {
      transform: scale(1.04);
      box-shadow: 0 0 0 4px #bae6fd, 0 8px 20px rgba(2, 132, 199, 0.35);
    }

    .main-idea-block.dimmed {
      opacity: 0.35;
    }

    /* Pillars / Details */
    .pillars-container {
      width: 82%;
      display: flex;
      justify-content: space-between;
      align-items: stretch;
      gap: 12px;
      height: 120px;
      z-index: 1;
    }

    .pillar {
      flex: 1;
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 6px;
      font-size: 14px;
      font-weight: 600;
      color: #475569;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
      transition: transform 0.3s ease, opacity 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
      cursor: pointer;
    }

    .pillar .icon {
      font-size: 18px;
      color: #0284c7;
    }

    .pillar.highlight {
      transform: translateY(-4px);
      border-color: #0284c7;
      color: #0284c7;
      box-shadow: 0 0 0 3px #bae6fd, 0 6px 14px rgba(2, 132, 199, 0.2);
    }

    .pillar.dimmed {
      opacity: 0.35;
    }

    /* Foundation / Topic */
    .foundation-block {
      width: 96%;
      height: 46px;
      background: #e2e8f0;
      border: 2px solid #cbd5e1;
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      font-size: 15px;
      color: #334155;
      transition: transform 0.3s ease, opacity 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
      z-index: 2;
    }

    .foundation-block.highlight {
      transform: scale(1.02);
      border-color: #0284c7;
      background: #f0f9ff;
      color: #0284c7;
      box-shadow: 0 0 0 3px #bae6fd;
    }

    .foundation-block.dimmed {
      opacity: 0.35;
    }

    /* Arrows indicating support */
    .arrow-group {
      position: absolute;
      top: 76px;
      width: 78%;
      display: flex;
      justify-content: space-between;
      pointer-events: none;
      opacity: 0.6;
    }

    .arrow-icon {
      flex: 1;
      text-align: center;
      font-size: 12px;
      color: #0284c7;
      font-weight: bold;
    }
  </style>
</head>
<body>

  
  <div class="nav-tabs">
    <button class="tab-btn active" data-mode="all">All</button>
    <button class="tab-btn" data-mode="main">Main Idea</button>
    <button class="tab-btn" data-mode="details">Details</button>
    <button class="tab-btn" data-mode="topic">Topic</button>
  </div>

  
  <div class="stage">
    
    <div id="mainBlock" class="main-idea-block">
      <span>Main Idea</span>
    </div>

    
    <div class="arrow-group">
      <div class="arrow-icon">▲</div>
      <div class="arrow-icon">▲</div>
      <div class="arrow-icon">▲</div>
    </div>

    
    <div class="pillars-container">
      <div class="pillar" data-pillar="1">
        <span class="icon">❚</span>
        <span>Detail</span>
      </div>
      <div class="pillar" data-pillar="2">
        <span class="icon">❚</span>
        <span>Detail</span>
      </div>
      <div class="pillar" data-pillar="3">
        <span class="icon">❚</span>
        <span>Detail</span>
      </div>
    </div>

    
    <div id="foundationBlock" class="foundation-block">
      <span>Topic</span>
    </div>
  </div>

  <script>
    const tabs = document.querySelectorAll('.tab-btn');
    const mainBlock = document.getElementById('mainBlock');
    const pillars = document.querySelectorAll('.pillar');
    const foundationBlock = document.getElementById('foundationBlock');

    function applyMode(mode) {
      // Clear states
      mainBlock.classList.remove('highlight', 'dimmed');
      foundationBlock.classList.remove('highlight', 'dimmed');
      pillars.forEach(p => p.classList.remove('highlight', 'dimmed'));

      if (mode === 'main') {
        mainBlock.classList.add('highlight');
        foundationBlock.classList.add('dimmed');
        pillars.forEach(p => p.classList.add('dimmed'));
      } else if (mode === 'details') {
        mainBlock.classList.add('dimmed');
        foundationBlock.classList.add('dimmed');
        pillars.forEach(p => p.classList.add('highlight'));
      } else if (mode === 'topic') {
        foundationBlock.classList.add('highlight');
        mainBlock.classList.add('dimmed');
        pillars.forEach(p => p.classList.add('dimmed'));
      }

      tabs.forEach(btn => {
        btn.classList.toggle('active', btn.dataset.mode === mode);
      });
    }

    tabs.forEach(btn => {
      btn.addEventListener('click', () => {
        applyMode(btn.dataset.mode);
      });
    });

    mainBlock.addEventListener('click', () => applyMode('main'));
    foundationBlock.addEventListener('click', () => applyMode('topic'));
    pillars.forEach(p => p.addEventListener('click', () => applyMode('details')));
  </script>
</body>
</html>

Once you know the big point, how do you know the author is telling the truth?

**Key details** are specific facts, reasons, and examples that directly prove and hold up the main idea.

Think of the main idea as a tabletop: without sturdy legs beneath it, the whole table crashes down.

<!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;
    }

    body {
      background: #f8f9fa;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 16px;
      min-height: 100%;
    }

    .header {
      text-align: center;
      margin-bottom: 8px;
    }

    .hint {
      font-size: 14px;
      color: #64748b;
      font-weight: 500;
    }

    .scene {
      position: relative;
      width: 100%;
      max-width: 420px;
      height: 220px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-end;
      padding-bottom: 24px;
    }

    .table-rig {
      position: absolute;
      top: 36px;
      width: 280px;
      height: 130px;
      transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
      transform-origin: center bottom;
    }

    .tabletop {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 38px;
      background: #0d9488;
      color: #ffffff;
      font-weight: 700;
      font-size: 15px;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 8px;
      box-shadow: 0 4px 12px rgba(13, 148, 136, 0.25);
      z-index: 2;
    }

    .legs-container {
      position: absolute;
      top: 38px;
      left: 0;
      width: 100%;
      height: 92px;
      display: flex;
      justify-content: space-between;
      padding: 0 20px;
    }

    .leg {
      width: 44px;
      height: 92px;
      background: #cbd5e1;
      border-radius: 0 0 6px 6px;
      display: flex;
      align-items: flex-end;
      justify-content: center;
      padding-bottom: 8px;
      font-size: 11px;
      font-weight: 600;
      color: #475569;
      transition: all 0.3s ease;
      opacity: 0.2;
      transform: translateY(-10px);
    }

    .leg.active {
      background: #0f766e;
      color: #ffffff;
      opacity: 1;
      transform: translateY(0);
      box-shadow: 0 4px 8px rgba(15, 118, 110, 0.2);
    }

    .floor {
      width: 100%;
      height: 4px;
      background: #e2e8f0;
      border-radius: 2px;
    }

    .status-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-size: 14px;
      font-weight: 700;
      padding: 6px 14px;
      border-radius: 20px;
      margin-top: 4px;
      transition: all 0.3s ease;
    }

    .status-supported {
      background: #ccfbf1;
      color: #0f766e;
    }

    .status-unstable {
      background: #fef3c7;
      color: #b45309;
    }

    .status-collapsed {
      background: #fee2e2;
      color: #b91c1c;
    }

    .controls {
      display: flex;
      gap: 8px;
      width: 100%;
      max-width: 420px;
      justify-content: center;
    }

    .btn-detail {
      flex: 1;
      border: 2px solid #e2e8f0;
      background: #ffffff;
      color: #64748b;
      padding: 10px 4px;
      border-radius: 10px;
      font-size: 13px;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 2px;
      transition: all 0.2s ease;
    }

    .btn-detail.active {
      border-color: #0d9488;
      background: #f0fdfa;
      color: #0d9488;
      box-shadow: 0 2px 6px rgba(13, 148, 136, 0.15);
    }

    .btn-detail .indicator {
      font-size: 11px;
    }
  </style>
</head>
<body>

  <div class="header">
    <div class="hint">Tap details to test support</div>
    <div id="statusBadge" class="status-badge status-supported">
      <span id="statusIcon">✓</span>
      <span id="statusText">Supported</span>
    </div>
  </div>

  <div class="scene">
    <div id="tableRig" class="table-rig">
      <div class="tabletop">Main Idea</div>
      <div class="legs-container">
        <div id="leg0" class="leg active">Detail</div>
        <div id="leg1" class="leg active">Detail</div>
        <div id="leg2" class="leg active">Detail</div>
      </div>
    </div>
    <div class="floor"></div>
  </div>

  <div class="controls">
    <button class="btn-detail active" id="btn0" onclick="toggleLeg(0)">
      <span>Detail 1</span>
      <span class="indicator">ON</span>
    </button>
    <button class="btn-detail active" id="btn1" onclick="toggleLeg(1)">
      <span>Detail 2</span>
      <span class="indicator">ON</span>
    </button>
    <button class="btn-detail active" id="btn2" onclick="toggleLeg(2)">
      <span>Detail 3</span>
      <span class="indicator">ON</span>
    </button>
  </div>

  <script>
    const state = [true, true, true];

    function toggleLeg(index) {
      state[index] = !state[index];
      render();
    }

    function render() {
      // Update leg visuals & buttons
      for (let i = 0; i < 3; i++) {
        const leg = document.getElementById('leg' + i);
        const btn = document.getElementById('btn' + i);
        const ind = btn.querySelector('.indicator');

        if (state[i]) {
          leg.classList.add('active');
          btn.classList.add('active');
          ind.textContent = 'ON';
        } else {
          leg.classList.remove('active');
          btn.classList.remove('active');
          ind.textContent = 'OFF';
        }
      }

      const rig = document.getElementById('tableRig');
      const badge = document.getElementById('statusBadge');
      const statusIcon = document.getElementById('statusIcon');
      const statusText = document.getElementById('statusText');

      const count = state.filter(Boolean).length;
      badge.className = 'status-badge';

      if (count === 3 || (state[0] && state[2])) {
        // Perfectly balanced
        rig.style.transform = 'translateY(0) rotate(0deg)';
        badge.classList.add('status-supported');
        statusIcon.textContent = '✓';
        statusText.textContent = 'Supported';
      } else if (count === 2) {
        if (!state[0]) {
          // Left missing -> tilts left
          rig.style.transform = 'translateY(16px) rotate(-10deg)';
        } else if (!state[2]) {
          // Right missing -> tilts right
          rig.style.transform = 'translateY(16px) rotate(10deg)';
        }
        badge.classList.add('status-unstable');
        statusIcon.textContent = '⚠️';
        statusText.textContent = 'Unstable';
      } else if (count === 1) {
        if (state[1]) {
          rig.style.transform = 'translateY(18px) rotate(-14deg)';
        } else if (state[0]) {
          rig.style.transform = 'translateY(36px) rotate(18deg)';
        } else {
          rig.style.transform = 'translateY(36px) rotate(-18deg)';
        }
        badge.classList.add('status-unstable');
        statusIcon.textContent = '⚠️';
        statusText.textContent = 'Unstable';
      } else {
        // Collapsed completely
        rig.style.transform = 'translateY(68px) rotate(6deg)';
        badge.classList.add('status-collapsed');
        statusIcon.textContent = '✕';
        statusText.textContent = 'Collapsed';
      }
    }
  </script>
</body>
</html>

What does this look like when you tackle a real 4th-grade science passage?

Read this short passage: *The midnight ocean zone has freezing water and zero sunlight, yet animals find clever ways to survive. The anglerfish uses a glowing lure above its head to attract prey in the pitch dark. Meanwhile, the gulper eel has an enormous stretchy mouth that lets it swallow prey much larger than itself. Some deep-sea shrimp even spray glowing clouds of fluid to blind predators while they escape.*

First, find the **topic**: deep-sea animals. Next, look at what all the sentences have in common to find the **main idea**.

<!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>Topic, Main Idea, and Details</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      user-select: none;
      -webkit-user-select: none;
    }

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

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

    /* Interactive Stepper Navigation */
    .nav-tabs {
      display: flex;
      gap: 6px;
      width: 100%;
      justify-content: center;
    }

    .tab-btn {
      background: #f1f5f9;
      border: 1px solid #e2e8f0;
      color: #64748b;
      font-size: 13px;
      font-weight: 600;
      padding: 6px 14px;
      border-radius: 20px;
      cursor: pointer;
      transition: all 0.25s ease;
    }

    .tab-btn.active {
      background: #10b981;
      border-color: #10b981;
      color: #ffffff;
      box-shadow: 0 2px 8px rgba(16, 185, 129, 0.3);
    }

    /* Visual Hierarchy Structure */
    .structure-container {
      width: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 10px;
      position: relative;
    }

    /* 1. TOPIC (Broadest Layer) */
    .topic-pill {
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 30px;
      padding: 6px 18px;
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 700;
      color: #475569;
      transition: all 0.3s ease;
      box-shadow: 0 2px 4px rgba(0,0,0,0.03);
    }

    .topic-pill.highlight {
      border-color: #0ea5e9;
      background: #f0f9ff;
      color: #0369a1;
      box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.2);
    }

    .connector-down {
      width: 2px;
      height: 12px;
      background: #cbd5e1;
      transition: background 0.3s ease;
    }

    .connector-down.highlight {
      background: #10b981;
    }

    /* 2. MAIN IDEA (Central Umbrella) */
    .main-idea-box {
      width: 100%;
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 12px;
      padding: 12px 16px;
      text-align: center;
      transition: all 0.3s ease;
      box-shadow: 0 2px 4px rgba(0,0,0,0.03);
    }

    .main-idea-box.highlight {
      border-color: #10b981;
      background: #ecfdf5;
      box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
    }

    .box-tag {
      font-size: 11px;
      font-weight: 800;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      margin-bottom: 2px;
      color: #94a3b8;
      transition: color 0.3s ease;
    }

    .main-idea-box.highlight .box-tag {
      color: #059669;
    }

    .box-title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
    }

    /* 3. SUPPORTING DETAILS (Pillars) */
    .details-row {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      width: 100%;
    }

    .detail-card {
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 10px;
      padding: 10px 6px;
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      transition: all 0.3s ease;
      box-shadow: 0 2px 4px rgba(0,0,0,0.03);
    }

    .detail-card.highlight {
      border-color: #8b5cf6;
      background: #f5f3ff;
      box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.2);
    }

    .detail-card .icon {
      font-size: 20px;
      line-height: 1;
    }

    .detail-card .text {
      font-size: 12px;
      font-weight: 600;
      color: #334155;
      line-height: 1.2;
    }

    .detail-card.highlight .text {
      color: #5b21b6;
    }

    /* Playback bar */
    .controls {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 4px;
    }

    .play-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      width: 32px;
      height: 32px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      font-size: 12px;
      color: #475569;
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Can you spot the most common trick question on reading tests?

A common mistake is choosing an exciting fact—like *the glowing lure of the anglerfish*—as the entire main idea.

A single detail is too narrow because it only describes one sentence, not the whole passage.

Before picking your answer, always ask: *Does this statement cover the whole text, and do the other sentences back it up?*

Reading Informational Texts at the Grade 4-5 Level. Read grade 4-5 level informational texts independently and understand the main idea and key details.

Supporting a Main Idea with Key Details | 4th Grade Reading & Vocab

Determine the Main Idea of a Passage (Grade 4 ELA Skill Practice)

Main Idea & Key Details Comprehension Passages & Lesson Units (Grades 4-5 Band)

To foster independence in reading Grade 4–5 complex informational texts (RI.4.10), use the 'Gradual Release of Responsibility' model (I Do, We Do, You Do). Scaffold complex domain-specific vocabulary before independent reading using morphology and context clue strategies. Pair passages with graphic organizers (like the Tabletop or Funnel models) to prevent students from confusing high-interest trivia with the central thesis. Transition students from single-paragraph analysis to multi-paragraph expository texts by having them annotate section sub-ideas in the margins before consolidating them into an overarching text summary.

Reading Informational Texts at the Grade 4-5 Level

The Topic vs. The Main Idea

Supporting Details: The Table Legs