We used a ball bounce investigation as the basis for the instruction. We learned the importance of keeping variables the same by demonstrating how unfair it is to add force to one ball but not the other, to drop them from different heights, and to drop them on different surfaces (carpet and tile). Students then had the opportunity to drop two different balls (we used ping pong balls, tennis balls, basketballs, soccer balls, kickballs, super balls, and racquet balls) from eye level and report their results to the class.
It turns out that it was a great lesson to learn about measurement (meters vs. yards, kilometers vs. miles, measuring in centimeters, etc.). We also worked on the idea that scientists are accurate. This helped improve our observing skills and overall effort. Students finally got down on the floor to see where the underside of each ball bounced up to on our meter sticks after lots of reminders about scientific accuracy!
Once all of the data were recorded, students were asked to find mean averages of the results. I reminded them that they had to add up the data from each trial for each ball and divide by the total number of trials. They asked about what to do with the remainder, so it was a great opportunity to discuss how remainders can be reported as fractions or decimals within an authentic context. Finally, I had them subtract the averages to see how much higher one ball bounced than the other.
We reported out to the class and I assigned a reflective blog entry as homework. They needed to tell us a couple things that they learned during the lesson and restate their results. Here is a sample (they aren't due until Friday, so not everyone has done it yet):
If I didn't choose to have my students do this written reflection, I wouldn't have as clear a picture of their learning as I do now. I asked them to try to wow me with their details and information and I think this student did. As I look for evidence of prior knowledge being combined with what was learned today, I struggle to find it (other than her incorrect prediction that the basketball would bounce higher than a ping pong ball). That tells me that most of what was learned today was new to her. That's great! I'm glad to see my students learning in my presence!