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docs/reference/js/lessons/spinner/activity.md

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+# spinner activity
+
+create an arrow that randomly points to a player. #docs
+
+To create a new script, go to the [Create Code](/microbit/create-code) page and tap *New Project* under **Touch Develop**.
+
+Let's begin by adding an `input->on shake` condition to know when the BBC micro:bit is shaken.
+
+```
+input.onGesture(Gesture.Shake, () => {
+})
+```
+
+Now let's randomly generate a number from 0 to 3 so that we can randomly display an arrow in a given direction.
+
+```
+input.onGesture(Gesture.Shake, () => {
+    let randomArrow = Math.random(4)
+})
+```
+
+Now let's handle each of the cases by displaying the appropriate arrow. (Let's display an up arrow if `random arrow` is 0.
+
+```
+input.onGesture(Gesture.Shake, () => {
+    let randomArrow1 = Math.random(4)
+    if (randomArrow1 == 0) {
+        basic.showLeds(`
+. . # . .
+. # # # .
+# # # # #
+. . # . .
+. . # . .
+`, 400)
+    }
+})
+```
+
+Now let's handle the rest of the cases for `random arrow`.
+
+```
+input.onGesture(Gesture.Shake, () => {
+    let randomArrow2 = Math.random(4)
+    if (randomArrow2 == 0) {
+        basic.showLeds(`
+. . # . .
+. # # # .
+# # # # #
+. . # . .
+. . # . .
+`, 400)
+    } else if (randomArrow2 == 1) {
+        basic.showLeds(`
+. . # . .
+. . # . .
+# # # # #
+. # # # .
+. . # . .
+`, 400)
+    }
+    else if (randomArrow2 == 2) {
+        basic.showLeds(`
+. . # . .
+. . # # .
+# # # # #
+. . # # .
+. . # . .
+`, 400)
+    }
+    else if (randomArrow2 == 3) {
+        basic.showLeds(`
+. . # . .
+. # # . .
+# # # # #
+. # # . .
+. . # . .
+`, 400)
+    }
+})
+```
+
+### ~avatar avatar
+
+Excellent, you're ready to continue with the [challenges](/microbit/lessons/spinner/challenges)!
+
+### ~
+