diff --git a/01 - JavaScript Drum Kit/index-START.html b/01 - JavaScript Drum Kit/index-START.html
index 4070d32767..5c2d5a959f 100644
--- a/01 - JavaScript Drum Kit/index-START.html	
+++ b/01 - JavaScript Drum Kit/index-START.html	
@@ -59,8 +59,28 @@
 
 <script>
 
-</script>
+  function removeTransition(e) {
+    if (e.propertyName === 'transform') {
+      e.target.classList.remove('playing');
+    }
+  } 
+
+  function playSound(e) {
+    const audio = document.querySelector(`audio[data-key="${e.keyCode}"]`);
+    const key = document.querySelector(`div[data-key="${e.keyCode}"]`);
+    
+    if (audio && key) {
+      key.classList.add('playing');
+      audio.currentTime = 0;
+      audio.play();
+    }
+  }
 
+  const keys = Array.from(document.querySelectorAll('.key'));
+  keys.forEach(key => key.addEventListener('transitionend', removeTransition));
+  window.addEventListener('keydown', playSound);
+
+</script>
 
 </body>
 </html>
diff --git a/02 - JS + CSS Clock/index-START.html b/02 - JS + CSS Clock/index-START.html
index 2712384201..0448d3d720 100644
--- a/02 - JS + CSS Clock/index-START.html	
+++ b/02 - JS + CSS Clock/index-START.html	
@@ -9,9 +9,9 @@
 
     <div class="clock">
       <div class="clock-face">
-        <div class="hand hour-hand"></div>
-        <div class="hand min-hand"></div>
-        <div class="hand second-hand"></div>
+        <div class="hand hour-hand slow"></div>
+        <div class="hand minute-hand slow"></div>
+        <div class="hand second-hand slow"></div>
       </div>
     </div>
 
@@ -61,12 +61,51 @@
       background:black;
       position: absolute;
       top:50%;
+      transform-origin: 100%;
+      transform: rotate(90deg);
+      transition: all 0.05s;
+      transition-timing-function: cubic-bezier(0, 2.76, 0.9, 0.01);
+    }
+
+    .slow {
+      transition: all 0.8s;
+    }
+
+    .second-hand {
+      background: red;
     }
 
   </style>
 
   <script>
 
+    const secondHand  = document.querySelector('.second-hand');
+    const minuteHand  = document.querySelector('.minute-hand');
+    const hourHand    = document.querySelector('.hour-hand');
+
+    const hands = Array.from(document.querySelectorAll('.hand'));
+    hands.forEach(hand => hand.addEventListener('transitionend', removeSlowTransition));
+
+    window.onload = function() {
+      setInterval(setTime, 50);
+    }
+
+    function setTime(degrees) {
+      const now = new Date();
+
+      secondsDegrees = (now.getSeconds() / 60) * 360 + 90;
+      minutesDegrees = (now.getMinutes() / 60) * 360 + 90;
+      hoursDegrees = (now.getHours() / 12) * 360 + 90;
+
+      secondHand.style.transform = `rotate(${secondsDegrees}deg)`;
+      minuteHand.style.transform = `rotate(${minutesDegrees}deg)`;
+      hourHand.style.transform = `rotate(${hoursDegrees}deg)`;
+    }
+
+    function removeSlowTransition(e) {
+      e.target.classList.remove('slow');    
+      e.target.removeEventListener('transitionend', removeSlowTransition);
+    }
 
   </script>
 </body>
diff --git a/03 - CSS Variables/index-START.html b/03 - CSS Variables/index-START.html
index 7171607a8b..bd30929101 100644
--- a/03 - CSS Variables/index-START.html	
+++ b/03 - CSS Variables/index-START.html	
@@ -22,6 +22,22 @@ <h2>Update CSS Variables with <span class='hl'>JS</span></h2>
 
   <style>
 
+    :root {
+      --spacing: 10px;
+      --blur: 10px;
+      --base: lightGreen;
+    }
+
+    img {
+      padding: var(--spacing);
+      background: var(--base);
+      filter: blur(var(--blur));
+    }
+
+    .hl {
+      color: var(--base);
+    }
+
     /*
       misc styles, nothing to do with CSS variables
     */
@@ -48,6 +64,14 @@ <h2>Update CSS Variables with <span class='hl'>JS</span></h2>
   </style>
 
   <script>
+    const controls = document.querySelectorAll('.controls input');
+    controls.forEach(control => control.addEventListener('change', handleUpdate));
+    controls.forEach(control => control.addEventListener('mousemove', handleUpdate));
+
+    function handleUpdate() {
+      const sizing = this.dataset.sizing || '';
+      document.documentElement.style.setProperty(`--${this.name}`, this.value + sizing);
+    }
   </script>
 
 </body>