moving out outdated js docs

olddocs/js/lessons/blinks-rectangle/challenges.md

@@ -0,0 +1,79 @@
+# rectangle explosion challenges
+
+These challenges will allow you to make an exploding rectangle. #docs
+
+**Challenge 0**
+
+This [guided tutorial](https://test.microbit.co.uk/td/lessons/blinks-rectangle/tutorial) will help you show an animation forever!
+
+First, let's make a small rectangle blink forever.
+
+```blocks
+basic.forever(() => {
+    basic.showAnimation(`
+. . . . . . . . . .
+. # # # . . . . . .
+. # # # . . . . . .
+. . . . . . . . . .
+. . . . . . . . . .
+`, 400)
+})
+```
+
+**Challenge 1**
+
+Let's begin creating our explosion effect by adding another rectangle animation that displays a slightly larger rectangle after the first one.
+
+```
+basic.forever(() => {
+    basic.showAnimation(`
+. . . . . . . . . .
+. # # # . . . . . .
+. # # # . . . . . .
+. . . . . . . . . .
+. . . . . . . . . .
+`, 400)
+    basic.showAnimation(`
+. . . . . . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+. . . . . . . . . .
+`, 400) 
+})
+```
+
+**Challenge 2**
+
+To finalize our explosion effect, let's add a rectangle that is bigger than the last two we have created.
+
+```
+basic.forever(() => {
+    basic.showAnimation(`
+. . . . . . . . . .
+. # # # . . . . . .
+. # # # . . . . . .
+. . . . . . . . . .
+. . . . . . . . . .
+`, 400)
+    basic.showAnimation(`
+. . . . . . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+. . . . . . . . . .
+`, 400)
+    basic.showAnimation(`
+# # # # # . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+# # # # # . . . . .
+`, 400) 
+})
+```
+
+**Challenge 3**
+
+If you notice, the rectangle explodes fairly slow. Let's make it explode faster by decreasing the intervals of the animation from 400 to 200.
+