From 8f21967c2572131d9598c1cb1bc507038af29b75 Mon Sep 17 00:00:00 2001
From: Peter Wood <peter@peterwood.dev>
Date: Mon, 29 Sep 2025 17:01:31 -0400
Subject: [PATCH] added skip counting by 2

---
 margotwood/index.html          |  14 +
 margotwood/skipcount/twos.html | 471 +++++++++++++++++++++++++++++++++
 2 files changed, 485 insertions(+)
 create mode 100644 margotwood/skipcount/twos.html
diff --git a/margotwood/index.html b/margotwood/index.html
index 67d3d25..af2bcbc 100644
--- a/margotwood/index.html
+++ b/margotwood/index.html
@@ -183,6 +183,16 @@
     .app-link.subtraction:active {
       background: linear-gradient(135deg, #38f9d7 0%, #43e97b 100%);
     }
+
+    /* Skip counting-specific styling */
+    .app-link.skip-counting {
+      background: linear-gradient(135deg, #ff9a9e 0%, #fecfef 100%);
+    }
+
+    .app-link.skip-counting:hover,
+    .app-link.skip-counting:active {
+      background: linear-gradient(135deg, #fecfef 0%, #ff9a9e 100%);
+    }
   </style>
 </head>
 
@@ -199,6 +209,10 @@
       <div class="emoji">➖</div>
       <div class="link-text">Subtraction</div>
     </a>
+    <a href="skipcount/twos.html" class="app-link skip-counting">
+      <div class="emoji">⏭️ 2️⃣</div>
+      <div class="link-text">Skip Counting by 2s</div>
+    </a>
     <div class="footer">
       <p>Fun math games for little learners! 🌟</p>
     </div>
diff --git a/margotwood/skipcount/twos.html b/margotwood/skipcount/twos.html
new file mode 100644
index 0000000..9696b6a
--- /dev/null
+++ b/margotwood/skipcount/twos.html
@@ -0,0 +1,471 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Toddler Math Flash Cards - Skip Counting by 2s!</title>
+    <link href="https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700;800&display=swap" rel="stylesheet">
+    <style>
+        * {
+            margin: 0;
+            padding: 0;
+            box-sizing: border-box;
+        }
+
+        body {
+            font-family: 'Nunito', sans-serif;
+            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+            min-height: 100vh;
+            display: flex;
+            justify-content: center;
+            align-items: flex-start;
+            color: #333;
+            padding: 10px 0;
+        }
+
+        .app-container {
+            background: white;
+            border-radius: 20px;
+            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
+            padding: 20px;
+            text-align: center;
+            max-width: 500px;
+            width: 95%;
+            margin: 10px auto;
+        }
+
+        .title {
+            color: #4a5568;
+            font-size: 2.2em;
+            margin-bottom: 15px;
+            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
+        }
+
+        .flashcard {
+            background: linear-gradient(135deg, #ff9a9e 0%, #fecfef 100%);
+            border-radius: 15px;
+            padding: 25px;
+            margin: 15px 0;
+            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
+            transition: transform 0.3s ease;
+        }
+
+        .flashcard:hover {
+            transform: scale(1.05);
+        }
+
+        .equation {
+            font-size: 3.5em;
+            font-weight: bold;
+            color: white;
+            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
+            margin-bottom: 10px;
+        }
+
+        .sequence-display {
+            font-size: 2.2em;
+            font-weight: bold;
+            color: white;
+            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
+            margin-bottom: 15px;
+            line-height: 1.2;
+        }
+
+        .answer-section {
+            margin: 20px 0;
+        }
+
+        .answer-input {
+            font-size: 2.5em;
+            padding: 12px 15px;
+            border: 4px solid #667eea;
+            border-radius: 15px;
+            text-align: center;
+            width: 130px;
+            margin: 0 auto 15px auto;
+            display: block;
+            font-family: 'Nunito', sans-serif;
+        }
+
+        .answer-input:focus {
+            outline: none;
+            border-color: #ff9a9e;
+            box-shadow: 0 0 20px rgba(255, 154, 158, 0.3);
+        }
+
+        .buttons {
+            display: flex;
+            gap: 15px;
+            justify-content: center;
+            margin-top: 20px;
+        }
+
+        .btn {
+            font-size: 1.5em;
+            padding: 15px 30px;
+            border: none;
+            border-radius: 50px;
+            cursor: pointer;
+            font-family: 'Nunito', sans-serif;
+            font-weight: bold;
+            transition: all 0.3s ease;
+            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
+        }
+
+        .btn-check {
+            background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
+            color: white;
+        }
+
+        .btn-next {
+            background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
+            color: white;
+        }
+
+        .btn:hover {
+            transform: translateY(-3px);
+            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
+        }
+
+        .feedback {
+            font-size: 2.5em;
+            font-weight: bold;
+            margin: 20px 0;
+            padding: 20px;
+            border-radius: 15px;
+            transition: all 0.5s ease;
+        }
+
+        .correct {
+            background: linear-gradient(135deg, #84fab0 0%, #8fd3f4 100%);
+            color: #2d5a27;
+        }
+
+        .incorrect {
+            background: linear-gradient(135deg, #ffecd2 0%, #fcb69f 100%);
+            color: #8b4513;
+        }
+
+        .score {
+            background: rgba(255, 255, 255, 0.9);
+            padding: 8px 15px;
+            border-radius: 20px;
+            font-size: 1em;
+            font-weight: bold;
+            color: #4a5568;
+            margin-bottom: 15px;
+            display: inline-block;
+        }
+
+        .celebration {
+            font-size: 3em;
+            animation: bounce 1s infinite;
+        }
+
+        @keyframes bounce {
+
+            0%,
+            20%,
+            50%,
+            80%,
+            100% {
+                transform: translateY(0);
+            }
+
+            40% {
+                transform: translateY(-30px);
+            }
+
+            60% {
+                transform: translateY(-15px);
+            }
+        }
+
+        .number-buttons {
+            display: grid;
+            grid-template-columns: repeat(4, 1fr);
+            gap: 10px;
+            margin: 15px 0;
+        }
+
+        .number-buttons .number-btn:last-child {
+            grid-column: span 2;
+        }
+
+        .number-btn {
+            font-size: 1.8em;
+            padding: 12px;
+            border: 3px solid #667eea;
+            border-radius: 12px;
+            background: white;
+            cursor: pointer;
+            font-family: 'Nunito', sans-serif;
+            font-weight: bold;
+            color: #667eea;
+            transition: all 0.2s ease;
+            min-height: 50px;
+        }
+
+        .number-btn:hover {
+            background: #667eea;
+            color: white;
+            transform: scale(1.1);
+        }
+
+        .hint {
+            font-size: 1.2em;
+            color: #666;
+            margin-bottom: 10px;
+            font-style: italic;
+        }
+
+        @media (max-width: 600px) {
+            .app-container {
+                padding: 15px;
+                margin: 5px auto;
+            }
+
+            .title {
+                font-size: 1.8em;
+                margin-bottom: 10px;
+            }
+
+            .equation {
+                font-size: 2.8em;
+            }
+
+            .sequence-display {
+                font-size: 1.8em;
+            }
+
+            .answer-input {
+                font-size: 2.2em;
+                width: 110px;
+            }
+
+            .number-btn {
+                font-size: 1.6em;
+                padding: 10px;
+                min-height: 45px;
+            }
+
+            .btn {
+                font-size: 1.3em;
+                padding: 12px 25px;
+            }
+        }
+
+        @media (max-height: 700px) {
+            .flashcard {
+                padding: 20px;
+                margin: 10px 0;
+            }
+
+            .equation {
+                font-size: 3em;
+            }
+
+            .sequence-display {
+                font-size: 2em;
+            }
+
+            .number-btn {
+                font-size: 1.6em;
+                padding: 8px;
+                min-height: 40px;
+            }
+        }
+    </style>
+</head>
+
+<body>
+    <div class="app-container">
+        <div class="score" id="score">Score: 0/0</div>
+        <h1 class="title">⏭️ Skip Counting by 2s</h1>
+
+        <div class="flashcard">
+            <div class="hint">What comes next?</div>
+            <div class="sequence-display" id="sequenceDisplay">2, 4, 6, ?</div>
+        </div>
+
+        <div class="answer-section">
+            <input type="number" class="answer-input" id="answerInput" placeholder="?" min="0" max="100">
+
+            <div class="number-buttons" id="numberButtons">
+                <button class="number-btn" onclick="inputNumber(0)">0</button>
+                <button class="number-btn" onclick="inputNumber(1)">1</button>
+                <button class="number-btn" onclick="inputNumber(2)">2</button>
+                <button class="number-btn" onclick="inputNumber(3)">3</button>
+                <button class="number-btn" onclick="inputNumber(4)">4</button>
+                <button class="number-btn" onclick="inputNumber(5)">5</button>
+                <button class="number-btn" onclick="inputNumber(6)">6</button>
+                <button class="number-btn" onclick="inputNumber(7)">7</button>
+                <button class="number-btn" onclick="inputNumber(8)">8</button>
+                <button class="number-btn" onclick="inputNumber(9)">9</button>
+                <button class="number-btn" onclick="inputNumber(10)">10</button>
+                <button class="number-btn" onclick="clearAnswer()"
+                    style="background: #ff6b6b; color: white;">Clear</button>
+            </div>
+        </div>
+
+        <div class="feedback" id="feedback" style="display: none;"></div>
+
+        <div class="buttons">
+            <button class="btn btn-check" onclick="checkAnswer()">Check Answer! 🎯</button>
+            <button class="btn btn-next" onclick="nextCard()" style="display: none;" id="nextBtn">Next Card! ➡️</button>
+        </div>
+    </div>
+
+    <script>
+        let currentSequence = [];
+        let correctAnswer;
+        let totalQuestions = 0;
+        let correctAnswers = 0;
+        let sequenceLength = 3; // Start with 3 numbers shown, ask for 4th
+
+        function generateNewCard() {
+            // Generate a random starting point for skip counting by 2s
+            // Start with even numbers from 0 to 10, then continue the sequence
+            const startNumber = Math.floor(Math.random() * 6) * 2; // 0, 2, 4, 6, 8, 10
+
+            // Create sequence of specified length
+            currentSequence = [];
+            for (let i = 0; i < sequenceLength; i++) {
+                currentSequence.push(startNumber + (i * 2));
+            }
+
+            // The correct answer is the next number in the sequence
+            correctAnswer = startNumber + (sequenceLength * 2);
+
+            // Display the sequence with a question mark for the next number
+            const sequenceDisplay = currentSequence.join(', ') + ', ?';
+            document.getElementById('sequenceDisplay').textContent = sequenceDisplay;
+
+            // Reset the input and feedback
+            document.getElementById('answerInput').value = '';
+            document.getElementById('feedback').style.display = 'none';
+            document.getElementById('nextBtn').style.display = 'none';
+
+            // Don't focus on input to prevent keyboard from showing on mobile
+        }
+
+        function inputNumber(num) {
+            const input = document.getElementById('answerInput');
+            const currentValue = input.value;
+
+            if (currentValue === '' || currentValue === '0') {
+                input.value = num;
+            } else if (currentValue.length < 3) { // Limit to 3 digits max for larger numbers
+                input.value = currentValue + num;
+            }
+        }
+
+        function clearAnswer() {
+            document.getElementById('answerInput').value = '';
+        }
+
+        function checkAnswer() {
+            const userAnswer = parseInt(document.getElementById('answerInput').value);
+            const feedbackEl = document.getElementById('feedback');
+
+            if (isNaN(userAnswer)) {
+                alert('Please enter a number! 😊');
+                return;
+            }
+
+            totalQuestions++;
+
+            if (userAnswer === correctAnswer) {
+                correctAnswers++;
+                feedbackEl.innerHTML = `<div class="celebration">🎉</div>Perfect! The sequence is: ${currentSequence.join(', ')}, ${correctAnswer}`;
+                feedbackEl.className = 'feedback correct';
+
+                // Play success sound (if browser supports it)
+                playSound('success');
+
+                // Gradually increase difficulty by showing longer sequences
+                if (correctAnswers % 5 === 0 && sequenceLength < 5) {
+                    sequenceLength++;
+                }
+            } else {
+                feedbackEl.innerHTML = `<div>Try again! 💪</div>The sequence is: ${currentSequence.join(', ')}, ${correctAnswer}`;
+                feedbackEl.className = 'feedback incorrect';
+
+                // Play try again sound (if browser supports it)
+                playSound('tryAgain');
+            }
+
+            feedbackEl.style.display = 'block';
+            document.getElementById('nextBtn').style.display = 'inline-block';
+
+            updateScore();
+        }
+
+        function nextCard() {
+            generateNewCard();
+        }
+
+        function updateScore() {
+            const percentage = totalQuestions > 0 ? Math.round((correctAnswers / totalQuestions) * 100) : 0;
+            document.getElementById('score').textContent = `Score: ${correctAnswers}/${totalQuestions} (${percentage}%)`;
+        }
+
+        function playSound(type) {
+            // Create audio context for simple beep sounds
+            try {
+                const audioContext = new (window.AudioContext || window.webkitAudioContext)();
+                const oscillator = audioContext.createOscillator();
+                const gainNode = audioContext.createGain();
+
+                oscillator.connect(gainNode);
+                gainNode.connect(audioContext.destination);
+
+                if (type === 'success') {
+                    // Happy ascending notes
+                    oscillator.frequency.setValueAtTime(523.25, audioContext.currentTime); // C5
+                    oscillator.frequency.setValueAtTime(659.25, audioContext.currentTime + 0.1); // E5
+                    oscillator.frequency.setValueAtTime(783.99, audioContext.currentTime + 0.2); // G5
+                } else {
+                    // Gentle encouraging tone
+                    oscillator.frequency.setValueAtTime(440, audioContext.currentTime); // A4
+                }
+
+                gainNode.gain.setValueAtTime(0, audioContext.currentTime);
+                gainNode.gain.linearRampToValueAtTime(0.1, audioContext.currentTime + 0.01);
+                gainNode.gain.exponentialRampToValueAtTime(0.01, audioContext.currentTime + 0.3);
+
+                oscillator.start(audioContext.currentTime);
+                oscillator.stop(audioContext.currentTime + 0.3);
+            } catch (e) {
+                // Audio not supported, silent fail
+            }
+        }
+
+        // Keyboard support
+        document.getElementById('answerInput').addEventListener('keypress', function (e) {
+            if (e.key === 'Enter') {
+                if (document.getElementById('nextBtn').style.display === 'none') {
+                    checkAnswer();
+                } else {
+                    nextCard();
+                }
+            }
+        });
+
+        // Initialize the first card when page loads
+        window.onload = function () {
+            generateNewCard();
+            updateScore();
+        };
+
+        // Prevent negative numbers
+        document.getElementById('answerInput').addEventListener('input', function (e) {
+            if (e.target.value < 0) {
+                e.target.value = 0;
+            }
+        });
+    </script>
+</body>
+
+</html>
