Use "and wait" blocks to use blocks that execute sequentially in Scratch.

Students can get confused when they use multiple play-sound blocks in a row because if you don’t use the play-sound- until-done blocks the sounds start one after another before the previous sound can finish playing. Students can also get confused when broadcasting messages because there are broadcast blocks and broadcast-and- wait blocks. I recommend students use "until done" or "and wait" so that their blocks of code execute sequentially.

Example: "Remember to use the broadcast and wait block."

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