Due to the fact that I have been out on medical leave since January and will be out for a few more weeks, I conducted this lesson and lab with my 10 year old son. He is in the fourth grade and this is why I chose a fourth grade standard. Although, I also think the students in my moderately disabled class would very much enjoy this lesson and be able to participate fully. Not to mention the variety of textures for sensory. My son very much enjoyed this lab and especially the discussion on roller coasters. He was also able to make the connection to vehicles and types of tires and driving surfaces. He also talked about snow chains and ice on roads even though we live in a climate that doesn’t get much winter precipitation. My son always asks lots of questions, so this was a perfect unit for him. We started off with the movie on friction and played the online game. With both of these, he was totally engaged. I tried to get my younger son to participate as well, but he is only seven and didn’t fully understand. Our discussion of roller coasters was fun and engaging, but I can see that in a classroom with 25-30 students it would be difficult for the students to stay focused on friction and roller coasters rather than the rides themselves. I kept having to get my son back on track. Maybe in the future I would change this in some way so that it is a small group discussion where they need to point out 3 things that affect roller coasters and friction with a time limit.
For the lab itself, my son was able to create his hypothesis of which would provide the highest friction to the lowest. He made the connection at the end that his hypothesis was disproved as to the order of highest to lowest friction. It also took us several attempts to create a slope that would work for all of the surfaces. It was a pretty steep slope in order for the block to slide on the sandpaper and rubber. Unfortunately, on the carpet the block had a tendency to roll rather than slide and on the rubber, it didn’t want to go at all or roll once and bounce down the rest of the way. I think the corners on my block should also be well rounded next time. The sharp corners made the block have more of a tendency to roll and bounce on the carpet and rubber rather than slide. Depending on the abilities of the class, or for higher grades studying friction and force, I think this lab could be modified to measure force in Newtons and calculate friction and force as opposed to timing it. I think this would allow an even more scientific basis for the idea of friction and force and without the effects of gravity.
At the end of the lab experiment, I was pleased with the conclusions my son made. He was able to graph his results (with a little help) and determine the highest to lowest friction based on the visual results from the graph and the timed results from the table. The final question from the lab, was what other variables might effect friction. He stated the type of carpet, such as short pile or long pile, a smooth surface or bumpy (more so than sandpaper), and the steepness of the slope.
I will post the work sample tomorrow since I saved it as a PDF rather than a JPEG and I can't figure out how to get the PDF in here. Does anybody know? Copy and paste didn't work.
