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docs/lessons/snowflake-fall/activity.md

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+# snowflake fall blocks activity
+
+design a blinking rectangle animation. #docs #tutorials #stepByStep
+
+### ~avatar avatar
+
+### @video td/videos/snowflake-fall-0
+
+Welcome! This tutorial will teach how design a **snowfall animation**. Let's get started!
+
+### ~
+
+Let's start by creating a `forever` loop that will allow us to repeat the show LEDs code. Any code in the `forever` loop will repeat in the background... forever.
+
+
+```blocks
+basic.forever(() => {
+    basic.showLeds(`
+        . . . . .
+        . . # . .
+        . # # # .
+        . . # . .
+        . . . . .
+        `)
+    basic.showLeds(`
+        . . . . .
+        . . . . .
+        . . . . .
+        . . . . .
+        . . . . .
+        `)
+})
+```
+
+The next step is to add two `show LEDs` blocks inside the `forever` loop to repeat an animation.
+
+```blocks
+basic.forever(() => {
+    basic.showLeds(`
+        . . . . .
+        . . # . .
+        . # # # .
+        . . # . .
+        . . . . .
+        `)
+    basic.showLeds(`
+        . . # . .
+        . # . # .
+        # . . . #
+        . # . # .
+        . . # . .
+        `)
+})
+```blocks
+
+Run your code in the simulator or download it to your BBC micro:bit to see what happens!
+
+### ~avatar avatar
+
+Excellent, you're ready to continue with the [challenges](/microbit/lessons/snowflake-fall/challenges)!
+
+### ~
+