Fun Hands-On Geometry Lesson for Kinder and First

At this time of year attention spans are short so it is always good to bring in a fun hands on activity. Why not use shapes to make new figures? I used this for an enrichment unit to see which of my students could demonstrate different perspectives in an enrichment class, but you could easily use it to meet these common core standards for kinder and first graders.

Kinder: CC KB6: Compose simple shapes to form larger shapes.

1st: CC standard 1GA2: Compose two-dimensional shapes (rectangles, squares, trapezoids, triangles, … to create a composite shape, and compose new shapes from the composite shape.¹

This will take a little preparation because you will need four right triangles cut out of card stock. Each triangle needs to be of a different color. I used the Ellison die cutter at school and cut out squares. Then with a sharp pair of scissors, I cut down the middle of the square to make 2 triangles. Of course remind students to take care of the triangles so you can use them over and over. I chose not to laminate because I felt the plastic edges would probably make the shapes not fit together very well.

Next, you pose several different figures for the students to make. Students have to use all four triangles for each figure.

1. build a square.
2. build a triangle.
3. build a rectangle.
4. build mountains.
5. build a diamond (really just the same as a square but turned differently. See if your students know to do this.
6. build a house
7. build a pinwheel (if you attempt this one be prepared to show students a picture of a pinwheel. This one proved to be most difficult for students because even after they had built it, they had the triangles turned the wrong direction and thought they were correct.)

Solutions are below.

I had my students sit on a circle around the carpet and build their figures. Some of them looked at others work to help them. If you really want to know who knows what, then this configuration wouldn’t work well, but at times, I think it was helpful for students to see their peers work. I liked sitting in a circle around the carpet because I wanted to see the students closely during this time.

Alternately, you could tell the students to build as many different figures as possible with four right triangles and record them as they find each solution. This could be done on a separate day. Heres a link that shows the ways and other activities to do with right triangles.

The four triangles