My kid is in pre-school and on each week one of the kids presents a profession, mine chose to present microbiologist (I tried to talk him out of it). Besides demonstrating what microbiologists do, they (we) need to come up with some activity so I will give him some plates to grow bacteria on but I thought I'll come up with another more "active" activity, maybe demonstrating how fast bacteria grow. Any suggestion for how to do that? Any suggestion for other bacteria-related activity? The kids are 5-6 years old.
Have you seen the demos of a laser pointer and a drop of pond water? I bet that would interest kids. Of course--safety first--no laser pointers to eyeballs.
Here's one sample: http://www.teachertube.com/viewVideo.php?video_id=129632 and another setup with less overhead:
I think just getting across the idea of teeny things you can't normally see live in water might be sufficient at that level.