# snowflake fall blocks lesson design a blinking rectangle animation. ### @video td/videos/snowflake-fall-0 ## Topic Forever ## Quick Links * [activity](/microbit/lessons/snowflake-fall/activity) * [quiz](/microbit/lessons/snowflake-fall/quiz) * [quiz answers](/microbit/lessons/snowflake-fall/quiz-answers) * [challenges](/microbit/lessons/snowflake-fall/challenges) ## Prior learning/place of lesson in scheme of work Learn how to show LEDs with a, `pause` to pause program execution for a specified amount of milliseconds. We will be learning how to show images using forever loop as well as simple commands, such as pause and show LEDs. ## Documentation * **show LEDs** : [read more...](/microbit/reference/basic/show-leds) * **pause** : [read more...](/microbit/reference/basic/pause) * **forever** : [read more...](/microbit/reference/basic/forever) ```cards basic.showLeds(` . . . . . . . . . . . . # . . . . . . . . . . . . `) basic.pause(100) basic.forever(() => {}) ```