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Imagine finding a handful of shiny coins in your piggy bank! How do you know how much candy or toys each one can buy?

We measure coin values in **cents**. The cent sign looks like a little **¢**.

Let's meet the only brown coin in your pocket first!

A **penny** has a copper-brown color and features **Abraham Lincoln** on the front. A penny is worth **1¢** (one cent).

<!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>Identifying Coins</title>
  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
  <style>
    body {
      background-color: #fef9f3;
      color: #1e2945;
      font-family: system-ui, -apple-system, sans-serif;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    .selector-bar {
      display: flex;
      gap: 8px;
      width: 100%;
      max-width: 420px;
      justify-content: center;
      margin-bottom: 12px;
    }

    .coin-tab {
      flex: 1;
      padding: 8px 4px;
      background: #ffffff;
      border: 2px solid #e6e6e6;
      border-radius: 12px;
      font-size: 13px;
      font-weight: 700;
      color: #6b7280;
      cursor: pointer;
      text-align: center;
      transition: all 0.2s ease;
    }

    .coin-tab.active {
      border-color: #b87333;
      color: #1e2945;
      background: #fff8f0;
      box-shadow: 0 2px 8px rgba(184, 115, 51, 0.15);
    }

    .stage {
      width: 100%;
      max-width: 420px;
      background: #ffffff;
      border-radius: 16px;
      border: 1px solid #eee4dc;
      padding: 16px;
      display: flex;
      flex-direction: column;
      align-items: center;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.03);
    }

    .coin-viewport {
      height: 130px;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      width: 100%;
    }

    /* Coin Models */
    .coin {
      border-radius: 50%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      box-shadow: inset 0 2px 4px rgba(255, 255, 255, 0.6), inset 0 -3px 5px rgba(0, 0, 0, 0.3), 0 6px 14px rgba(0, 0, 0, 0.15);
      position: absolute;
      transition: opacity 0.3s ease;
      opacity: 0;
      pointer-events: none;
    }

    .coin.active {
      opacity: 1;
      pointer-events: auto;
    }

    .coin-penny {
      width: 96px;
      height: 96px;
      background: radial-gradient(circle at 35% 30%, #e89c68, #b87333 55%, #7a421a);
      border: 3px solid #8e491c;
      color: #4a2206;
    }

    .coin-nickel {
      width: 106px;
      height: 106px;
      background: radial-gradient(circle at 35% 30%, #f8fafc, #cbd5e1 55%, #64748b);
      border: 4px solid #94a3b8;
      color: #334155;
    }

    .coin-dime {
      width: 88px;
      height: 88px;
      background: radial-gradient(circle at 35% 30%, #f8fafc, #cbd5e1 55%, #64748b);
      border: 3px solid #94a3b8;
      color: #334155;
    }

    .coin-quarter {
      width: 122px;
      height: 122px;
      background: radial-gradient(circle at 35% 30%, #ffffff, #d1d5db 55%, #6b7280);
      border: 4px dashed #9ca3af;
      color: #1f2937;
    }

    .coin-val-main {
      font-size: 20px;
      font-weight: 800;
      line-height: 1;
      text-shadow: 0 1px 1px rgba(255, 255, 255, 0.5);
    }

    .coin-subtext {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-top: 3px;
      opacity: 0.85;
    }

    /* Comparison Details */
    .details-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      width: 100%;
      margin-top: 12px;
      padding-top: 12px;
      border-top: 1px solid #f0ebe4;
    }

    .detail-pill {
      background: #fdfaf6;
      border: 1px solid #f0e6dc;
      border-radius: 10px;
      padding: 8px 4px;
      text-align: center;
    }

    .detail-label {
      font-size: 11px;
      font-weight: 600;
      color: #8c827a;
      text-transform: uppercase;
      margin-bottom: 2px;
    }

    .detail-value {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
    }

    /* Size Comparison Scale */
    .scale-row {
      display: flex;
      align-items: flex-end;
      justify-content: space-around;
      width: 100%;
      max-width: 420px;
      margin-top: 12px;
      padding: 8px 12px;
      background: #ffffff;
      border-radius: 12px;
      border: 1px solid #eee4dc;
    }

    .scale-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      cursor: pointer;
    }

    .mini-coin {
      border-radius: 50%;
      box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
      transition: transform 0.2s ease, outline 0.2s ease;
    }

    .scale-item.active .mini-coin {
      outline: 3px solid #22b7ff;
      outline-offset: 2px;
    }

    .mini-dime {
      width: 22px;
      height: 22px;
      background: #cbd5e1;
      border: 2px solid #94a3b8;
    }

    .mini-penny {
      width: 25px;
      height: 25px;
      background: #b87333;
      border: 2px solid #8e491c;
    }

    .mini-nickel {
      width: 28px;
      height: 28px;
      background: #cbd5e1;
      border: 2px solid #94a3b8;
    }

    .mini-quarter {
      width: 32px;
      height: 32px;
      background: #cbd5e1;
      border: 2px solid #94a3b8;
    }

    .scale-txt {
      font-size: 11px;
      font-weight: 700;
      color: #6b7280;
    }
  </style>
</head>
<body>

  
  <div class="selector-bar">
    <button class="coin-tab active" data-idx="0">Penny</button>
    <button class="coin-tab" data-idx="1">Nickel</button>
    <button class="coin-tab" data-idx="2">Dime</button>
    <button class="coin-tab" data-idx="3">Quarter</button>
  </div>

  
  <div class="stage">
    <div class="coin-viewport">
      
      <div class="coin coin-penny active" id="coin-0">
        <div class="coin-val-main">1¢</div>
        <div class="coin-subtext">Lincoln</div>
      </div>

      
      <div class="coin coin-nickel" id="coin-1">
        <div class="coin-val-main">5¢</div>
        <div class="coin-subtext">Jefferson</div>
      </div>

      
      <div class="coin coin-dime" id="coin-2">
        <div class="coin-val-main">10¢</div>
        <div class="coin-subtext">Roosevelt</div>
      </div>

      
      <div class="coin coin-quarter" id="coin-3">
        <div class="coin-val-main">25¢</div>
        <div class="coin-subtext">Washington</div>
      </div>
    </div>

    
    <div class="details-grid">
      <div class="detail-pill">
        <div class="detail-label">Value</div>
        <div class="detail-value" id="val-text">1¢</div>
      </div>
      <div class="detail-pill">
        <div class="detail-label">Color</div>
        <div class="detail-value" id="color-text">Copper</div>
      </div>
      <div class="detail-pill">
        <div class="detail-label">Size</div>
        <div class="detail-value" id="size-text">Medium</div>
      </div>
    </div>
  </div>

  
  <div class="scale-row">
    <div class="scale-item" data-idx="2">
      <div class="mini-coin mini-dime"></div>
      <span class="scale-txt">10¢</span>
    </div>
    <div class="scale-item active" data-idx="0">
      <div class="mini-coin mini-penny"></div>
      <span class="scale-txt">1¢</span>
    </div>
    <div class="scale-item" data-idx="1">
      <div class="mini-coin mini-nickel"></div>
      <span class="scale-txt">5¢</span>
    </div>
    <div class="scale-item" data-idx="3">
      <div class="mini-coin mini-quarter"></div>
      <span class="scale-txt">25¢</span>
    </div>
  </div>

  <script>
    const coinData = [
      { val: '1¢', color: 'Copper', size: 'Medium' },
      { val: '5¢', color: 'Silver', size: 'Thick' },
      { val: '10¢', color: 'Silver', size: 'Smallest' },
      { val: '25¢', color: 'Silver', size: 'Largest' }
    ];

    const tabs = $$('.coin-tab');
    const scaleItems = $$('.scale-item');
    const coins = [$('#coin-0'), $('#coin-1'), $('#coin-2'), $('#coin-3')];
    const valText = $('#val-text');
    const colorText = $('#color-text');
    const sizeText = $('#size-text');

    function selectCoin(idx) {
      tabs.forEach((tab, i) => tab.classList.toggle('active', i === idx));
      coins.forEach((coin, i) => coin.classList.toggle('active', i === idx));
      scaleItems.forEach(item => {
        const itemIdx = parseInt(item.getAttribute('data-idx'), 10);
        item.classList.toggle('active', itemIdx === idx);
      });

      valText.textContent = coinData[idx].val;
      colorText.textContent = coinData[idx].color;
      sizeText.textContent = coinData[idx].size;
    }

    tabs.forEach((tab, i) => {
      onTap(tab, () => selectCoin(i));
    });

    scaleItems.forEach(item => {
      onTap(item, () => {
        const idx = parseInt(item.getAttribute('data-idx'), 10);
        selectCoin(idx);
      });
    });
  </script>
</body>
</html>

What happens when a coin turns silver and gets a little thicker?

A **nickel** is silver-colored with a smooth, thick edge and features **Thomas Jefferson** on the front. It is worth **5¢** (five cents), which equals 5 pennies.

<!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>US Coins Comparison</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: #f8f9fa;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    /* Tab Buttons */
    .coin-tabs {
      display: flex;
      gap: 6px;
      width: 100%;
      max-width: 440px;
      justify-content: center;
    }
    .tab-btn {
      flex: 1;
      padding: 8px 4px;
      border: 1px solid #d1d5db;
      background: #ffffff;
      border-radius: 12px;
      font-size: 13px;
      font-weight: 600;
      color: #4b5563;
      cursor: pointer;
      text-align: center;
      transition: all 0.2s ease;
      box-shadow: 0 1px 2px rgba(0,0,0,0.04);
    }
    .tab-btn.active {
      background: #708090;
      color: #ffffff;
      border-color: #708090;
      box-shadow: 0 2px 6px rgba(112, 128, 144, 0.35);
    }

    /* Showcase Display */
    .showcase {
      display: flex;
      flex-direction: column;
      align-items: center;
      width: 100%;
      max-width: 440px;
      background: #ffffff;
      border-radius: 16px;
      padding: 14px 12px;
      box-shadow: 0 2px 8px rgba(0,0,0,0.06);
      margin: 10px 0;
      position: relative;
    }

    .coin-stage {
      height: 110px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 8px;
    }

    /* Realistic Coin Styles */
    .coin-disc {
      border-radius: 50%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      box-shadow: inset 0 2px 4px rgba(255,255,255,0.7), inset 0 -2px 5px rgba(0,0,0,0.25), 0 4px 8px rgba(0,0,0,0.18);
      transition: all 0.25s ease;
      position: relative;
      user-select: none;
    }
    .coin-disc::after {
      content: '';
      position: absolute;
      inset: 4px;
      border-radius: 50%;
      border: 1px dashed rgba(0,0,0,0.15);
      pointer-events: none;
    }

    .copper {
      background: radial-gradient(circle at 35% 30%, #f6b48f, #b86b3e 65%, #8d481f 95%);
      color: #5a2808;
      border: 2px solid #a3592c;
    }
    .silver {
      background: radial-gradient(circle at 35% 30%, #ffffff, #dcdfe3 55%, #9aa0a6 95%);
      color: #374151;
      border: 2px solid #b0b7bd;
    }

    .coin-label {
      font-size: 11px;
      font-weight: 700;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      opacity: 0.85;
    }
    .coin-val {
      font-size: 20px;
      font-weight: 800;
      line-height: 1.1;
    }

    /* Badges Row */
    .badges-row {
      display: flex;
      gap: 6px;
      justify-content: center;
      margin-bottom: 10px;
    }
    .badge {
      font-size: 11px;
      font-weight: 600;
      padding: 3px 8px;
      border-radius: 20px;
      background: #f1f5f9;
      color: #475569;
      border: 1px solid #e2e8f0;
    }

    /* Penny Count Grid */
    .equivalence-box {
      width: 100%;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 8px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 6px;
    }
    .eq-header {
      font-size: 12px;
      font-weight: 700;
      color: #334155;
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .pennies-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 3px;
      justify-content: center;
      max-width: 320px;
      min-height: 24px;
      align-items: center;
    }
    .mini-penny {
      width: 16px;
      height: 16px;
      border-radius: 50%;
      background: radial-gradient(circle at 35% 30%, #f6b48f, #b86b3e);
      border: 1px solid #8d481f;
      color: #ffffff;
      font-size: 8px;
      font-weight: 800;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 1px 2px rgba(0,0,0,0.15);
    }

    /* Bottom Lineup */
    .lineup-card {
      width: 100%;
      max-width: 440px;
      background: #ffffff;
      border-radius: 14px;
      padding: 8px 10px;
      box-shadow: 0 1px 4px rgba(0,0,0,0.05);
    }
    .lineup-title {
      font-size: 11px;
      font-weight: 700;
      color: #64748b;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      text-align: center;
      margin-bottom: 6px;
    }
    .lineup-row {
      display: flex;
      justify-content: space-around;
      align-items: flex-end;
      padding-top: 4px;
    }
    .lineup-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      cursor: pointer;
      padding: 4px 6px;
      border-radius: 8px;
      transition: background 0.15s;
    }
    .lineup-item:hover {
      background: #f1f5f9;
    }
    .lineup-item.active {
      background: #f1f5f9;
      box-shadow: inset 0 0 0 1.5px #708090;
    }
    .lineup-item .mini-disc {
      border-radius: 50%;
      box-shadow: 0 2px 4px rgba(0,0,0,0.15);
    }
    .lineup-val {
      font-size: 11px;
      font-weight: 700;
      color: #1e2945;
    }
  </style>
</head>
<body>

  
  <div class="coin-tabs">
    <button class="tab-btn" onclick="selectCoin(0)">Penny</button>
    <button class="tab-btn active" onclick="selectCoin(1)">Nickel</button>
    <button class="tab-btn" onclick="selectCoin(2)">Dime</button>
    <button class="tab-btn" onclick="selectCoin(3)">Quarter</button>
  </div>

  
  <div class="showcase">
    <div class="coin-stage">
      <div id="coinDisc" class="coin-disc silver" style="width: 86px; height: 86px;">
        <span id="coinPortrait" class="coin-label">Jefferson</span>
        <span id="coinVal" class="coin-val">5¢</span>
      </div>
    </div>

    <div class="badges-row">
      <span id="badgeColor" class="badge">Silver</span>
      <span id="badgeEdge" class="badge">Smooth Edge</span>
      <span id="badgeSize" class="badge">21.2 mm</span>
    </div>

    
    <div class="equivalence-box">
      <div id="eqHeader" class="eq-header">1 Nickel = 5 Pennies</div>
      <div id="penniesGrid" class="pennies-grid"></div>
    </div>
  </div>

  
  <div class="lineup-card">
    <div class="lineup-title">Actual Relative Sizes</div>
    <div class="lineup-row">
      <div class="lineup-item" onclick="selectCoin(0)">
        <div class="mini-disc copper" style="width: 32px; height: 32px;"></div>
        <span class="lineup-val">1¢</span>
      </div>
      <div class="lineup-item active" onclick="selectCoin(1)">
        <div class="mini-disc silver" style="width: 36px; height: 36px;"></div>
        <span class="lineup-val">5¢</span>
      </div>
      <div class="lineup-item" onclick="selectCoin(2)">
        <div class="mini-disc silver" style="width: 30px; height: 30px;"></div>
        <span class="lineup-val">10¢</span>
      </div>
      <div class="lineup-item" onclick="selectCoin(3)">
        <div class="mini-disc silver" style="width: 42px; height: 42px;"></div>
        <span class="lineup-val">25¢</span>
      </div>
    </div>
  </div>

  <script>
    const coins = [
      {
        name: "Penny",
        plural: "Pennies",
        valNum: 1,
        valStr: "1¢",
        portrait: "Lincoln",
        colorType: "copper",
        colorLabel: "Copper",
        edge: "Smooth Edge",
        sizeMm: "19.0 mm",
        pxSize: 76
      },
      {
        name: "Nickel",
        plural: "Nickels",
        valNum: 5,
        valStr: "5¢",
        portrait: "Jefferson",
        colorType: "silver",
        colorLabel: "Silver",
        edge: "Smooth Edge",
        sizeMm: "21.2 mm",
        pxSize: 86
      },
      {
        name: "Dime",
        plural: "Dimes",
        valNum: 10,
        valStr: "10¢",
        portrait: "Roosevelt",
        colorType: "silver",
        colorLabel: "Silver",
        edge: "Ridged Edge",
        sizeMm: "17.9 mm",
        pxSize: 72
      },
      {
        name: "Quarter",
        plural: "Quarters",
        valNum: 25,
        valStr: "25¢",
        portrait: "Washington",
        colorType: "silver",
        colorLabel: "Silver",
        edge: "Ridged Edge",
        sizeMm: "24.3 mm",
        pxSize: 98
      }
    ];

    let currentIdx = 1;

    function selectCoin(idx) {
      currentIdx = idx;
      const c = coins[idx];

      // Update Tabs
      const tabs = document.querySelectorAll('.tab-btn');
      tabs.forEach((tab, i) => {
        tab.classList.toggle('active', i === idx);
      });

      // Update Lineup
      const lineupItems = document.querySelectorAll('.lineup-item');
      lineupItems.forEach((item, i) => {
        item.classList.toggle('active', i === idx);
      });

      // Update Showcase Coin
      const disc = document.getElementById('coinDisc');
      disc.className = `coin-disc ${c.colorType}`;
      disc.style.width = c.pxSize + 'px';
      disc.style.height = c.pxSize + 'px';

      document.getElementById('coinPortrait').textContent = c.portrait;
      document.getElementById('coinVal').textContent = c.valStr;

      // Update Badges
      document.getElementById('badgeColor').textContent = c.colorLabel;
      document.getElementById('badgeEdge').textContent = c.edge;
      document.getElementById('badgeSize').textContent = c.sizeMm;

      // Update Equivalence Box
      const eqHeader = document.getElementById('eqHeader');
      if (c.valNum === 1) {
        eqHeader.textContent = "1 Penny = 1¢";
      } else {
        eqHeader.textContent = `1 ${c.name} = ${c.valNum} Pennies`;
      }

      // Populate mini pennies
      const grid = document.getElementById('penniesGrid');
      grid.innerHTML = '';
      for (let i = 0; i < c.valNum; i++) {
        const mini = document.createElement('div');
        mini.className = 'mini-penny';
        mini.textContent = '1';
        grid.appendChild(mini);
      }
    }

    // Initialize with Nickel (matches pre-text context)
    selectCoin(1);
  </script>
</body>
</html>

If a nickel is worth 5 cents, is a smaller coin worth less?

A **dime** is the smallest and thinnest coin of all, but it is mighty! One dime is worth **10¢** (ten cents).

Don't let size fool you: even though a dime is smaller than a penny and a nickel, it is worth more than both of them!

<!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;
      background: #ffffff;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
      padding: 16px 8px;
    }

    /* Mode switcher */
    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 20px;
      background: #f1f5f9;
      padding: 4px;
      border-radius: 999px;
    }
    .btn {
      border: none;
      background: transparent;
      padding: 6px 16px;
      border-radius: 999px;
      font-size: 14px;
      font-weight: 600;
      color: #64748b;
      cursor: pointer;
      transition: all 0.25s ease;
    }
    .btn.active {
      background: #2563eb;
      color: #ffffff;
      box-shadow: 0 2px 6px rgba(37, 99, 235, 0.25);
    }

    /* Main stage */
    .stage {
      display: flex;
      justify-content: center;
      align-items: flex-end;
      gap: 12px;
      width: 100%;
      max-width: 480px;
      height: 240px;
      padding-bottom: 24px;
      border-bottom: 2px solid #e2e8f0;
    }

    /* Coin Column */
    .coin-col {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-end;
      flex: 1;
      height: 100%;
      transition: order 0.4s ease, transform 0.3s ease;
    }

    /* Realistic Relative Coin Sizes */
    /* Dime: 17.9mm (~54px) | Penny: 19.0mm (~58px) | Nickel: 21.2mm (~65px) | Quarter: 24.3mm (~76px) */
    .coin {
      border-radius: 50%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.12), inset 0 2px 4px rgba(255,255,255,0.6);
      position: relative;
      user-select: none;
      border: 2px dashed rgba(0,0,0,0.15);
    }

    .coin-penny {
      width: 58px;
      height: 58px;
      background: radial-gradient(circle at 35% 35%, #f97316, #b45309);
      color: #ffffff;
    }
    .coin-nickel {
      width: 65px;
      height: 65px;
      background: radial-gradient(circle at 35% 35%, #f1f5f9, #94a3b8);
      color: #334155;
    }
    .coin-dime {
      width: 54px;
      height: 54px;
      background: radial-gradient(circle at 35% 35%, #ffffff, #cbd5e1);
      color: #1e293b;
      outline: 3px solid #2563eb;
      outline-offset: 3px;
    }
    .coin-quarter {
      width: 76px;
      height: 76px;
      background: radial-gradient(circle at 35% 35%, #ffffff, #94a3b8);
      color: #1e293b;
    }

    .coin-val {
      font-size: 15px;
      line-height: 1;
    }
    .coin-name {
      font-size: 10px;
      font-weight: 600;
      opacity: 0.85;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    /* Comparison Bar / Value Visualizer */
    .val-bar-wrap {
      width: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      margin-top: 12px;
      height: 100px;
      justify-content: flex-end;
    }

    .val-bar {
      width: 22px;
      background: #e2e8f0;
      border-radius: 4px 4px 0 0;
      transition: height 0.4s ease, background 0.3s ease;
    }

    .coin-col.highlight .val-bar {
      background: #2563eb;
    }

    .rank-label {
      margin-top: 6px;
      font-size: 12px;
      font-weight: 700;
      color: #64748b;
    }

    /* Summary Indicator */
    .caption {
      margin-top: 14px;
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .badge {
      background: #dbeafe;
      color: #1d4ed8;
      padding: 2px 8px;
      border-radius: 6px;
      font-size: 12px;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <button class="btn active" id="btnValue" onclick="setMode('value')">Order by Value</button>
    <button class="btn" id="btnSize" onclick="setMode('size')">Order by Size</button>
  </div>

  
  <div class="stage" id="stage">
    
    
    <div class="coin-col" id="col-penny">
      <div class="coin coin-penny">
        <span class="coin-val">1¢</span>
        <span class="coin-name">Penny</span>
      </div>
      <div class="val-bar-wrap">
        <div class="val-bar" style="height: 12px;"></div>
        <span class="rank-label">1¢</span>
      </div>
    </div>

    
    <div class="coin-col" id="col-nickel">
      <div class="coin coin-nickel">
        <span class="coin-val">5¢</span>
        <span class="coin-name">Nickel</span>
      </div>
      <div class="val-bar-wrap">
        <div class="val-bar" style="height: 24px;"></div>
        <span class="rank-label">5¢</span>
      </div>
    </div>

    
    <div class="coin-col highlight" id="col-dime">
      <div class="coin coin-dime">
        <span class="coin-val">10¢</span>
        <span class="coin-name">Dime</span>
      </div>
      <div class="val-bar-wrap">
        <div class="val-bar" style="height: 48px;"></div>
        <span class="rank-label">10¢</span>
      </div>
    </div>

    
    <div class="coin-col" id="col-quarter">
      <div class="coin coin-quarter">
        <span class="coin-val">25¢</span>
        <span class="coin-name">Quarter</span>
      </div>
      <div class="val-bar-wrap">
        <div class="val-bar" style="height: 90px;"></div>
        <span class="rank-label">25¢</span>
      </div>
    </div>

  </div>

  
  <div class="caption" id="caption">
    <span>Dime:</span>
    <span class="badge">Smallest Size</span>
    <span>≠</span>
    <span class="badge">Smallest Value</span>
  </div>

  <script>
    const colDime = document.getElementById('col-dime');
    const colPenny = document.getElementById('col-penny');
    const colNickel = document.getElementById('col-nickel');
    const colQuarter = document.getElementById('col-quarter');
    const btnValue = document.getElementById('btnValue');
    const btnSize = document.getElementById('btnSize');

    function setMode(mode) {
      if (mode === 'size') {
        btnSize.classList.add('active');
        btnValue.classList.remove('active');
        // Sort by physical diameter: Dime (54px) < Penny (58px) < Nickel (65px) < Quarter (76px)
        colDime.style.order = '1';
        colPenny.style.order = '2';
        colNickel.style.order = '3';
        colQuarter.style.order = '4';
      } else {
        btnValue.classList.add('active');
        btnSize.classList.remove('active');
        // Sort by monetary value: Penny (1¢) < Nickel (5¢) < Dime (10¢) < Quarter (25¢)
        colPenny.style.order = '1';
        colNickel.style.order = '2';
        colDime.style.order = '3';
        colQuarter.style.order = '4';
      }
    }

    // Set initial order by value
    setMode('value');
  </script>
</body>
</html>

Now, what is the biggest common coin in your pocket?

A **quarter** is the largest and heaviest coin, with a ridged edge and **George Washington** on the front. It is worth **25¢** (twenty-five cents).

One quarter equals $25$ pennies, $5$ nickels, or $2\text{ dimes} + 1\text{ nickel}$.

One quarter is equal in value to **25 pennies**, **5 nickels**, or **2 dimes and 1 nickel**.

Let's line up all four coins from the smallest value to the biggest value.

<!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>Coin Values and Sizes</title>
<style>
  * { box-sizing: border-box; margin: 0; padding: 0; }
  body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: transparent;
    color: #1e2945;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100%;
    padding: 12px;
    gap: 16px;
  }

  .value-bar {
    width: 100%;
    max-width: 580px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 14px;
    background: #f1f5f9;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 700;
    color: #64748b;
  }
  .value-bar span {
    display: flex;
    align-items: center;
    gap: 4px;
  }
  .value-bar .arrow {
    color: #16a34a;
    font-size: 16px;
  }

  .coins-grid {
    width: 100%;
    max-width: 580px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
  }

  .coin-card {
    background: #ffffff;
    border: 2px solid #e2e8f0;
    border-radius: 16px;
    padding: 12px 6px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    height: 200px;
    cursor: pointer;
    transition: box-shadow 0.2s ease, border-color 0.2s ease;
    user-select: none;
  }

  .coin-card.active {
    border-color: #22b7ff;
    box-shadow: 0 4px 14px rgba(34, 183, 255, 0.25);
  }

  .coin-slot {
    height: 90px;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  /* Physically proportional coin representations */
  .coin {
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    color: rgba(0,0,0,0.65);
    text-shadow: 0 1px 0 rgba(255,255,255,0.4);
    box-shadow: inset 0 2px 4px rgba(255,255,255,0.6), inset 0 -2px 4px rgba(0,0,0,0.25), 0 3px 6px rgba(0,0,0,0.15);
    border: 2px dashed rgba(0,0,0,0.15);
  }

  /* Diameters: Dime(17.9mm) -> 54px, Penny(19mm) -> 60px, Nickel(21.2mm) -> 68px, Quarter(24.3mm) -> 80px */
  .coin-penny {
    width: 60px;
    height: 60px;
    background: radial-gradient(circle at 35% 35%, #e08c5c, #b35422);
    color: #4a1c04;
  }

  .coin-nickel {
    width: 68px;
    height: 68px;
    background: radial-gradient(circle at 35% 35%, #e2e8f0, #94a3b8);
    color: #334155;
  }

  .coin-dime {
    width: 54px;
    height: 54px;
    background: radial-gradient(circle at 35% 35%, #f8fafc, #cbd5e1);
    color: #334155;
  }

  .coin-quarter {
    width: 80px;
    height: 80px;
    background: radial-gradient(circle at 35% 35%, #f1f5f9, #94a3b8);
    color: #1e2945;
  }

  .coin-name {
    font-size: 14px;
    font-weight: 700;
    color: #1e2945;
  }

  .coin-val {
    font-size: 15px;
    font-weight: 800;
    color: #16a34a;
    background: #dcfce7;
    padding: 3px 8px;
    border-radius: 10px;
  }

  .info-bar {
    width: 100%;
    max-width: 580px;
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 10px 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 14px;
    font-weight: 600;
    color: #334155;
    text-align: center;
    min-height: 44px;
  }

  .tag-pill {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 700;
  }
  .tag-copper { background: #ffedd5; color: #9a3412; }
  .tag-silver { background: #f1f5f9; color: #475569; }
  .tag-small { background: #e0f2fe; color: #0369a1; }
</style>
</head>
<body>

  <div class="value-bar">
    <span>Smallest Value (1¢)</span>
    <span class="arrow">→ → →</span>
    <span>Biggest Value (25¢)</span>
  </div>

  <div class="coins-grid">
    <div class="coin-card active" data-index="0" data-desc="Penny: Copper color, 1¢ value">
      <div class="coin-name">Penny</div>
      <div class="coin-slot">
        <div class="coin coin-penny">1¢</div>
      </div>
      <div class="coin-val">1¢</div>
    </div>

    <div class="coin-card" data-index="1" data-desc="Nickel: Thick silver coin, 5¢ value">
      <div class="coin-name">Nickel</div>
      <div class="coin-slot">
        <div class="coin coin-nickel">5¢</div>
      </div>
      <div class="coin-val">5¢</div>
    </div>

    <div class="coin-card" data-index="2" data-desc="Dime: Smallest size, 10¢ value">
      <div class="coin-name">Dime</div>
      <div class="coin-slot">
        <div class="coin coin-dime">10¢</div>
      </div>
      <div class="coin-val">10¢</div>
    </div>

    <div class="coin-card" data-index="3" data-desc="Quarter: Largest size, 25¢ value">
      <div class="coin-name">Quarter</div>
      <div class="coin-slot">
        <div class="coin coin-quarter">25¢</div>
      </div>
      <div class="coin-val">25¢</div>
    </div>
  </div>

  <div class="info-bar" id="infoBar">
    <span class="tag-pill tag-copper">Copper</span> Penny = 1¢
  </div>

<script>
  const cards = document.querySelectorAll('.coin-card');
  const info = document.getElementById('infoBar');

  const details = [
    '<span class="tag-pill tag-copper">Copper Color</span> Penny = 1¢',
    '<span class="tag-pill tag-silver">Silver Color</span> Nickel = 5¢',
    '<span class="tag-pill tag-small">Smallest Size</span> Dime = 10¢',
    '<span class="tag-pill tag-silver">Largest Size</span> Quarter = 25¢'
  ];

  let currentIdx = 0;
  let timer;

  function selectCoin(idx) {
    cards.forEach((c, i) => {
      c.classList.toggle('active', i === idx);
    });
    info.innerHTML = details[idx];
    currentIdx = idx;
  }

  cards.forEach((card, idx) => {
    card.addEventListener('click', () => {
      clearInterval(timer);
      selectCoin(idx);
      startAutoPlay();
    });
  });

  function startAutoPlay() {
    timer = setInterval(() => {
      currentIdx = (currentIdx + 1) % 4;
      selectCoin(currentIdx);
    }, 3200);
  }

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

Next time you see a coin, check its color and size to name it and shout out its value!

math

Identifying Pennies, Nickels, Dimes, and Quarters. Recognize and name common coins and state the cent value of each.

Counting American Coins & Identifying Coin Values

Coin Names and Values: Penny through Quarter

U.S. Coins for Kids: Identifying Pennies, Nickels, Dimes, and Quarters

At Early Level (P1), hands-on tactile manipulation of real or realistic play coins is essential. To dismantle the common misconception that physical size equals greater value (especially the Nickel vs. Dime paradox), pair each coin with concrete unit representations such as unifix cubes or ten-frame counters ($1\text{ cube} = 1\text{¢}$). Incorporate multisensory routines such as coin rubbings to explore textures/edges and interactive role-play classroom shops to fulfill the CfE standard (MNU 1-09b) of using coins in context.

Identifying Pennies, Nickels, Dimes, and Quarters

The Penny

The Nickel

The Dime