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docs/reference/js/lessons/digi-yoyo/challenges.md

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+# digi yoyo challenges
+
+Coding challenges for the digi yoyo. 
+
+## Before we get started
+
+Complete the following guided tutorial:
+
+* [tutorial](/microbit/lessons/digi-yoyo/tutorial)
+
+At the end of the tutorial, click `keep editing`. Your code should look like this:
+
+```
+let count = 0
+while (count < 10) {
+    basic.pause(1000)
+    basic.showNumber(count, 150)
+    count = count + 1
+}
+```
+
+### Challenge 1
+
+How about we create a counter that counts backwards from 10 to 1? Let's add a while loop that executes only when `count` is greater than 0.
+
+```
+let count1 = 0
+while (count1 < 10) {
+    basic.pause(1000)
+    basic.showNumber(count1, 150)
+    count1 = count1 + 1
+}
+while (count1 > 0) {
+}
+```
+
+### Challenge 2
+
+### @video td/videos/digi-yoyo-1-2
+
+Inside of the while loop, let's add `pause->(1000)` so that we have a pause between each number as it's counting down. Also, let's show `count`!
+
+```
+let count2 = 0
+while (count2 < 10) {
+    basic.pause(1000)
+    basic.showNumber(count2, 150)
+    count2 = count2 + 1
+}
+while (count2 > 0) {
+    basic.pause(1000) // ***
+    basic.showNumber(count2, 150) // ***
+}
+```
+
+* Run the code to see if it works as expected.
+
+### Challenge 3
+
+Now, we need `count` to decrease by one after the BBC micro:bit has displayed the value of `count`.
+
+We can do this by adding this line:
+
+`count := count - 1`
+