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docs/reference/js/lessons/screen-wipe/activity.md

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+# screen wipe activity
+
+Clear the screen by pressing buttons on the BBC micro:bit #docs #tutorials #stepByStep
+
+### ~avatar avatar
+
+### @video td/videos/screen-wipe-0
+
+This activity will teach how to clear the screen by pressing button ``A`` on the BBC micro:bit.
+
+### ~
+
+You can use the `basic->clear screen` function to turn off all the LED on the screen. Let's illustrate this concept with a small script where the user has to press the button ``A`` to turn off the screen. Let's start by adding the code to show an animation.
+
+```
+basic.showAnimation(`
+# # # # # # # # # # . . . . . . . . . .
+# # # # # # # # # # . . . . . . . . . .
+. . . . . # # # # # # # # # # . . . . .
+. . . . . # # # # # # # # # # # # # # #
+. . . . . . . . . . . . . . . # # # # #
+`, 400) // ***
+```
+
+We add another line of code that registers an **event handler** on the `input->on button pressed(A)` and calls `basic->clear screen`.
+
+```
+basic.showAnimation(`
+# # # # # # # # # # . . . . . . . . . .
+# # # # # # # # # # . . . . . . . . . .
+. . . . . # # # # # # # # # # . . . . .
+. . . . . # # # # # # # # # # # # # # #
+. . . . . . . . . . . . . . . # # # # #
+`, 400)
+input.onButtonPressed("A", () => {
+    basic.clearScreen() // ***
+}) // ***
+```
+
+Run the script in the simulator or on the BBC micro:bit to see how this works!
+
+### ~avatar boothing
+
+Excellent, you're ready to continue with the [challenges](/microbit/lessons/screen-wipe/challenges)!
+
+### ~
+