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Broadcast vs. "when background changes"?

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I always use broadcasts to make multiple things happen on one event, like when score = 15, broadcast "level2". Then when screen and sprites receive "level2", things change accordingly (background change, characters hide or show, etc.)

However, I've heard that some people just do it all on "when background changes". That would be a lot easier, since you don't have to send messages, have all the characters listen for specific messages, etc. I haven't tried it in a few years, but I recall getting unexpected results using this method. And I never got unexpected results from broadcasts.

Oh, and I'm using standalone Scratch 1.4 on the Raspberry Pi, if that makes a difference. 

Bob Irving
Porter-Gaud School
Charleston, SC
Thanks for the suggestion. I've signed up for the FB group. 

The unexpected results were that not everything that I wanted to happen actually happened. For instance -- go to level 2 = change background to level 2 background. Show some new sprites, speed up the old sprites, reset the timer, etc. Everything didn't work exactly as planned. But it always does with the broadcast. As I mentioned, though, I find the broadcast concept a tricky one for students to master.

However, sometimes you want a whole bunch of changes to happen (say, when a certain score is reached, a character goes off the screen, etc.) and you DON'T want to change the background. At that point, you really have to use a broadcast.

So I'm still pondering best approach. Thanks for the reply.
Hi Bob!
This is an interesting question. What types of unexpected results do you get? I wonder if it is a product of the actual approach, or whether it's something with the less updated version of Scratch?

Also, have you shared this question in the Teaching with Scratch Facebook Group? We're slowly migrating discussions over to there, and I think you'll find a lot of great support from the educators in the group!

Alexa, on behalf of the ScratchEd Team