Part of Lesson Plan: Attraction and Repulsion as a Gaming Principle in Scratch

Activity Overview / Details

At this point, students should already have had quite a bit of exposure to Scratch and should understand many of the underlying principles.

Check that students understand the following:

• how to move sprites using the mouse or keyboard
• how to check for the distance of one sprite to another
• how to make sprites move a set number of steps
• how to check for how many seconds have elapsed

A second idea involving how to reverse the roles of the sprites is important.  A variable should be declared which sets the number of steps a sprite moves.  After a set number of seconds have passed, multiply the variable by -1 (negative one).  This will reversed the movement of the sprites.

Sprite script:

Stage script: