Exploring Our Fluid Earth

I really enjoy your honesty and forthrightness. I particularly appreciated the comment on mixing up thte different density bags. I saw that some teachers added food coloring. I did as well. I found that helped keep track of the different bags. However, one should consider the affect of food coloring on the density of the liquid.

I apprecite your comment! I did use food coloring, and one group brought up how the coloing would affect densitiy, so we ran the exprment again without. However, I did find some kids weren't careful with their experimetation and did in fact mix up the different waters they collected (they reported hot fresh water sinking in cold salt for example). So we discussed "possible" sources of error and in some cases, re-ran experiments. btw - I did use and offer labels for keeping track...

Here is he Phase diagram for my DENSITY bags lesson.

Hi Vicki, just wondering if you had to adjust the time for your lesson. Did you repeat the lesson for several different classes or do it just for one class. I imagine that the lesson gets easier the more times you do it. Great job!