Start teaching Scratch with blocks that run for a set amount of time to avoid the common misconception that blocks are executed simultaneously.

Use the duration of these blocks to emphasize that the blocks are executed sequentially.
- For example, a script with three "play note _ for n beats" blocks will play each note for n beats, a total of three notes, in sequential order.
- Because it is obvious during the duration of each block that they are not running simultaneously, this will help remove this misconception.

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