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docs/reference/js/lessons/looper/challenges.md

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+# looper challenges
+
+Coding challenges for the looper tutorial. #docs
+
+## Before we get started
+
+Complete the following guided tutorial:
+
+* [tutorial](/microbit/lessons/looper/tutorial)
+
+At the end of the tutorial, click `keep editing`. Your code should look like this:
+
+```
+for (let i = 0; i < 6; i++) {
+    basic.showNumber(i, 150)
+    basic.pause(2000)
+}
+```
+
+### Challenge 1
+
+### @video td/videos/looper-1
+
+What if we want to count up to lucky number 7 instead? Let's do that by changing the ending value to `8` instead of `6`.
+
+```
+for (let i1 = 0; i1 < 8; i1++) {
+    basic.showNumber(i1, 150) // ***
+    basic.pause(2000)
+}
+```
+
+* Run the program now to see your changes.
+
+### Challenge 2
+
+### @video td/videos/looper-2
+
+What about 9? Let's do that by changing the ending value to `10`.
+
+```
+for (let i2 = 0; i2 < 10; i2++) {
+    basic.showNumber(i2, 150)
+    basic.pause(2000)
+}
+```
+
+* Run your code to see the new counter.
+
+### Challenge 3
+
+### @video td/videos/looper-3
+
+Now let's start counting from `3` instead! Our for loop will always start at `0` so we simply add `3` to the `i` variable when passing it to `basic->show number`.
+
+```
+for (let i3 = 0; i3 < 8; i3++) {
+    basic.showNumber(i3 + 3, 150) // ***
+    basic.pause(2000)
+}
+```
+
+Run it on the simulator!
+
+### Challenge 4
+
+### @video td/videos/looper-4
+
+Now, let's **count down from 9**. Change the line `basic->show number(i + 3, 150)` to `basic->show number(9 - i, 150)`.
+
+```
+for (let i4 = 0; i4 < 10; i4++) {
+    basic.showNumber(9 - i4, 150) // ***
+    basic.pause(2000)
+}
+```
+
+* Run the code to make sure it is doing what is expected.
+
+### Challenge 5
+
+After counting down from `9` let's show the string `BOOOM`!
+