## Rock Paper Scissors

Duration: ~20 minutes.

### Materials

• micro:bit, battery holder and 2 AAA batteries
• Roll of duct tape (maybe 2 rolls if you want another color)
• Velcro

### Activities

#### Setting

##### STEP 1 – CUT THE PIECES OF TAPE

Cut 2 Pieces of Duct Tape about 9-10 inches long. Press the sticky sides together to form one piece of tape (this is tricky!). This makes the band of your wrist cuff.

##### STEP 2 – ATTACH THE MICRO:BIT AND BATTERY PACK

Mount the micro:bit in the center of your wrist cuff band by looping a piece of duct tape around in a circle.

Attach the battery pack to the micro:bit and tape it on the wrist cuff band on the opposite side from the micro:bit.

##### STEP 3 – ADD THE WRIST FASTENERS THE MICRO:BIT

Attach Velcro tabs at the ends of the wrist cuff as fasteners. You may need to try it on your wrist to adjust the size.

##### STEP 4 – DECORATE IT!

Decorate the wrist cuff with stickers, glitter, markers, etc.

#### Code

##### STEP 1

We want the micro:bit to choose rock, paper, or scissors when you shake it. Place a `on shake`block so when you shake the micro:bit, it will run part of a program.

##### STEP 2

Add a `tool` variable to store a random number computed with `pick random`.

When you shake the micro:bit, it should pick a random number from `0` to `2` and store it in the variable `tool`. (This variable is named `tool` because rock, paper, and scissors are the tools you use to challenge your friends!)

In a later step, each of the possible numbers (0, 1, or 2) is matched to its own picture. The picture is shown on the LEDs when its number is picked.

##### STEP 3

Place an `if` block under the `pick random` and check whether `tool` is equal to `0`.

##### STEP 4

In the `if` block, place a `show leds` block that shows a picture of a piece of paper.

##### STEP 5

Add an `else if` block to the `if` block and check whether `tool` is equal to `1`. Click on the gearwheel icon to open up the `if` editor; then drag and drop an `else if` block in the `if`editor.

##### STEP 6

Place a `show leds` block under the else if and draw a rock image on the screen.

##### STEP 7

Add a `show leds` block with a picture of scissors to the `else` part. You don’t need to check if `tool` is `2` because `2` is the only number left out of `0``1`, and `2`. That’s why you can use an `else` instead of an `else if`.

Link of the whole program: https://makecode.microbit.org/_3kHLRkXR85s2