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docs/lessons/game-counter/challenges.md

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+# game counter challenges
+
+Coding challenges for the game counter. 
+
+## Before we get started
+
+Complete the following [activity](/microbit/lessons/game-counter/activity) . Your code should look like this:
+
+```blocks
+input.onButtonPressed(Button.A, () => {
+    game.addScore(1);
+    basic.showNumber(game.score())
+});
+```
+
+### Challenge 1
+
+### @video td/videos/counter-1-2
+
+Let's add the code to `score` when `B` is pressed. Add an event handler with `on button (B) pressed` then add the code to `score`.
+
+
+```blocks
+input.onButtonPressed(Button.A, () => {
+    game.addScore(1);
+    basic.showNumber(game.score())
+});
+
+input.onButtonPressed(Button.B, () => {
+    game.addScore(-1);
+    basic.showNumber(game.score())
+});
+```
+
+
+### Challenge 3
+
+Now let's try to reset the counter when the micro:bit is shaken. You will need to register an event handler with `on shake`.
+