How I Use It
I've used Osmos as a wrap-up to units on the Physics of motion. I go into great detail on Newton's three laws of motion, and students become very familiar with the theory behind Newtonian motion. They create presentations and practice them hands-on using graphs and stopwatches, heavy balls and rollers in the gym, etc. The Osmos app surprised me with how helpful and practical it was to use as a wrap-up or revisit to the unit. The physics engine is very accurate. Massive orbs take much force to get moving or to stop. Less substantial orbs accelerate more easily, with less wasted mass. Every action in Osmos does indeed have a reaction, and sometimes those reactions are unexpected.
I love the physics engine on this game. The practical, hands-on learning is an excellent way for me to check on whether my students understand and are able to apply Newton's Laws. It worked best for me as an informal assessment. I would get my students started on the game, and then simply walk the room and ask questions. "Why did you get so small now?" "What can you do to move that orb?" "How does this illustrate Newtons (insert number) law?" The surprises in the game also result in questions from students, like "Why did the other orb move away from me when I did that?" Or, "why is it so hard to get moving now?" I find it an excellent wrap-up exercise.