Teach the concept of a variable’s scope in Scratch by explaining the difference between “For this sprite only” and “For all sprites.”

Scope works a little differently in Scratch than in other languages. A variable that is "For this sprite only" can still be read by other sprites, but only the sprite that owns it can write to it. Variables that exist "For all sprites" act like global variables. This can help students when deciding what scope of variables to use for different tasks.

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