pxt-calliope/docs/lessons/rotation-animation.md

# rotation animation block lesson

Learn how to create images with a global variable and while loop.

## Topic

While Loop

## Quick links

* [activity](/lessons/rotation-animation/activity)
* [challenges](/lessons/rotation-animation/challenges)
* [quiz](/lessons/rotation-animation/quiz)
* [quiz answers](/lessons/rotation-animation/quiz-answers)

## Prior learning/place of lesson in scheme of work

Learn how to create images that look like a rotating animation by using a while loop. We will be learning how to create a rotating animation using a global variable, while loop as well as simple commands, such as on button pressed and show animation.

## Documentation

```cards
while (true) {}
let x = 0
input.onButtonPressed(Button.A, () => {})
basic.showLeds(`
    . . . . .
    . . . . .
    . . # . .
    . . . . .
    . . . . .
    `)
basic.pause(100)
```

## Objectives

* learn how to create a variable for a place where you can store data, accessible across functions, and in nested code blocks
* learn how to set or change the value of a  variable
* learn how to repeat code while a condition is true
* learn how to declare a boolean variable to determine which code will execute next
* learn how to run code when an input button is pressed
* learn how to show a series of image frames on the LED screen
* learn how to pause your code for the specified number of milliseconds