Friends, Patrons, and the Naturally Curious, This weekend, I finished the last (for now) tutorial for the Math Alive! class that I developed and taught for One Spark Academy. There may still be more of these tutorials someday. I dream of developing this into a big and colorful book. And I think it would be fun to do some stretch-and-squash with special relativity. But for now, this is it. [embed]https://youtu.be/2hi9Ngmzq5c[/embed] All the tutorials are now free on the web, right here. FREE! Check ‘em out, then give ‘em a whirl! Note that this is not the whole class, this is just the Scratch-specific portion. In addition to the Scratchwork, we also did a fair number of practice calculations on worksheets, as well as some astronomical running-around in which students took on the role of various objects moving under the influence of gravity. In the final tutorial, students add some UI features to the simulation - panning, zooming, and speed controls. It’s all done by keyboard, but these features let you focus on whatever you want to focus on. Which is nice. Here, you can see my model solar system with a terrestrial planet, a rocket-cat, a saturn-like planet, and a comet. If you keep an eye on the two scale variables at the top left, you can see how I tweak the zoom and the speed to accommodate the comet. After the comet makes its first pass by the sun, it swings out on a big slow orbit - so I zoom out the view to keep the comet in sight, then speed up the simulation so that I can watch it orbit in reasonable time. - Tim