What? Re-runs?

Yes, it's a re-run, but bear with me - - there's a plan. Everybody built (again) a molecular model of water. They all enjoyed the exact same exercise last spring, and they enjoyed it again. But the reason for bringing a rerun into our programming is that there's a whole lot we can get into about atoms and molecules, and this makes a perfect entry point. Really, the fact that I got a huge box of styro balls at a good price on eBay has nothing to do with it.

I also received in the Question Box a lovely set-up question about how clouds form. There is a whole lot in the Official Montessori Curriculum about states of matter and the water cycle, so this student has given us the opportunity to get into all that. Water – solid liquid gas – molecules – crystals -

And yes, the water molecule is shaped like Mickey Mouse.

It's intriguing how they completely get it and completely don't get it at the same time. The same child will give me signals that he knows exactly what I mean, and then more signals that he hasn't quite registered that this is anything other than a styro Mickey Mouse.
The tough concepts:
- what a scale model is
- how totally tiny a real atom is
Actually, I think most adults don’t get how tiny a real atom is. We can all work it out on paper, but it is difficult to impossible to really grasp it in the imagination, to visualize or feel it. There are about 602300000000000000000000 of these things in a teaspoonful of water. Really. Envision that number. Let me know when you've succeeded, because I can't do it.