Thursday, October 31, 2013

Find the Perimeter

It's been a world wind kind of nine weeks. I can't believe that it's the 2nd nine weeks already!! Before I know it, I will be driving back to Michigan to see my family for Christmas. My kids are pretty shocked too. We were getting ready to do an assignment and I told them that they are about 1/2 way done with 3rd grade--I almost had to pick up their jaws off the floor they were so surprised.

We just started our geometry unit in Math Investigations this week, and I am very pleased in how well everyone is doing. Who doesn't like to use a ruler to measure things?? Ha ha.

While on Pinterest, I found this cute song to help my students remember what a perimeter is, and not to confuse it with area. The "Perimeter Song" is to the tune of "Farmer and the Dell". In addition, we created an anchor chart together to show how to find the perimeter of shapes.




One of the lessons was an assessment on perimeter. They were to measure large shapes on the floor that were created out of tape. Since I really didn't want to put tape on my floor in order to create various shapes for the kiddos to measure, I put the shapes on chart paper. I was a perfect solution!! Also, the kids only had to give their group members a "check mark" on a rubric. I didn't like that either. I mean, if this is going to be an assessment (even an informal one) then I want to know that they are able to do the work in order to find the perimeter. I created another solution. Instead of use that stupid rubric, I made their chart paper a consensus map. The shape was in the middle and there was workspace marked off for each group member. Once they found the perimeter and agreed then they would write the perimeter in the middle of the shape. It worked out great!!



Once everyone was in a group, we talked out the rules:
1-EVERYONE had to measure each side. This is a way to double check out work.
2-Use the edge of the ruler to measure the edges of each side.
3-Write down each measurement.
4-EVERYONE is to find the perimeter in their own space.
5-Write the perimeter in the middle of the shape once everyone agrees.