- Generally, students will use wait blocks to create Knock-Knock joke conversations; however, broadcast blocks are much more appropriate in this context.
- Once students have created their Knock-Knock joke, ask them to arbitrarily change the timing of the conversation.
- The students will soon realize they have to change everything in order to change the timing.
- Introduce the broadcast block once they have changed the timing in a way that disrupts their program to demonstrate that it is necessary to use tools like broadcast blocks for dependent interactions.
- Note from the CS Teaching Tips Team: This strategy for introducing broadcast blocks is a pain point. Check out Sean Stern’s tip about another pain point in Scratch.