I've started a gallery of demo projects in response to forum questions about implementing Velocity, Gravity, Bouncing, etc. Projects will go from simple to more complex, I'll continue to add as I find time to build the projects.
http://scratch.mit.edu/galleries/view/9206
Please feel free to download to look at the projects and use whatever you like, and keep in mind that there are lots of different ways to do things in programming. There isn't a right or wrong way, so long as you get the result you want. You will likely learn more by looking at the demos, understanding what I did, and then trying to recreate or improve on them using some of your own ideas.
I'm a fan of descriptive names for variables and broadcasts, as well as lots of comments, which should help to make the demos understandable. Scratch on!
-Mr Ed
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