Today was our annual day of investigating distance vs. time graphs using CBR's (calculator based rangers) and graphing calculators. Students were in groups of 3-4. They had one handout that asked them to create specific graphs. Once they were successful, they needed to record a quick description of how they created the graph. In the end they needed to be able to explain what the difference was between a "straight" line and a "curved" line in terms of their walking. They also needed to justify why a few graphs were impossible.
Here are a few pictures of the events throughout the day.
Here are a few pictures of the events throughout the day.
The Goods:
Lots of student verbal communication. Listening to them tell each other to start closer, move slower, change direction, stop and wait, etc. was wonderful. I think they really understand the concept of initial starting value as well as the difference between a gradually slanted line and a steep line. The most common thing I overhead was "You need to go slower, your line is too steep." I also love this day because it lets them move and see how graphs actually are formed. They get a chance to get their 8th grade sillies out while investigating a very important topic - functions!
The Bads:
Space is tight and setting up 8 runs so each group can be small enough is tricky. This year I put tape on the floor to mark off each team's area. That helped a ton! We usually can get into a common larger area in our school, but this year it didn't happen. A view of my room is below. I had 6 runs going across the back and then 2 up in the front running perpendicular to the others. Fun stuff trying to get 30 kids engaged! The other bad was that there are always those kiddos that don't truly understand what they are doing. I had students trying to walk in a curved motion to graph a curved line. It was tough to get some of them to see that they needed to walk straight to get a curved line. Trying to get them to realize they needed to vary their speed was a hard job today without just telling them.
Lots of student verbal communication. Listening to them tell each other to start closer, move slower, change direction, stop and wait, etc. was wonderful. I think they really understand the concept of initial starting value as well as the difference between a gradually slanted line and a steep line. The most common thing I overhead was "You need to go slower, your line is too steep." I also love this day because it lets them move and see how graphs actually are formed. They get a chance to get their 8th grade sillies out while investigating a very important topic - functions!
The Bads:
Space is tight and setting up 8 runs so each group can be small enough is tricky. This year I put tape on the floor to mark off each team's area. That helped a ton! We usually can get into a common larger area in our school, but this year it didn't happen. A view of my room is below. I had 6 runs going across the back and then 2 up in the front running perpendicular to the others. Fun stuff trying to get 30 kids engaged! The other bad was that there are always those kiddos that don't truly understand what they are doing. I had students trying to walk in a curved motion to graph a curved line. It was tough to get some of them to see that they needed to walk straight to get a curved line. Trying to get them to realize they needed to vary their speed was a hard job today without just telling them.
My Favorite: My favorite part of this day is always watching groups try and create a step function. This year I had a group of girls do something I've never seen a group do - kick over chairs. The video here is not the original group that tried it, but one of the others that watched and learned and recreated. So much learning going on! | |
The way students normally tackle graphing the step function is in the second video, to the right. This takes them a while to actually figure out. They usually start out just jumping backwards or running across where the motion detector is detecting. So interesting to watch and listen to them thinking out loud! | |
This whole lesson was shown to me many years ago by a college professor, Char Beckmann, at Grand Valley State University. I've tweaked it over the years, but so much of it is credited to her!