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docs/reference/js/lessons/for-loop/challenges.md

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+# looper challenges
+
+These challenges will allow you to create a counter from 0-5 and then from 5-0. #docs
+
+### Challenge 0
+
+Welcome! This [guided tutorial](/microbit/bcvgkf) will assist you with the following activity:
+
+```
+for (let i = 0; i < 6; i++) {
+    led.showNumber(i, 150)
+    basic.pause(2000)
+}
+```
+
+### Challenge 1
+
+Go through the loop faster by changing the length of the pause. This is the line you will be editing: `basic->pause(2000)`
+
+```
+for (let i1 = 0; i1 < 6; i1++) {
+    basic.showNumber(i1, 150)
+    basic.pause(500) // ***
+}
+```
+
+### Challenge 2
+
+Now, let's count down from 5 instead of counting up to 5. Change the line `basic->show number(i, 150)` to `basic->show number(5 - i, 150)`.
+
+```
+for (let i2 = 0; i2 < 6; i2++) {
+    basic.showNumber(5 - i2, 150) // ***
+    basic.pause(2000)
+}
+```
+
+### Challenge 3
+
+Have the number count up in 2's from zero. It should go: 0, 2, 4, 6, 8, 10.
+