Part 1: Students learned the names of several polygons in his classroom (quadrilateral, triangle etc.) in the beginning of the year. To activate this prior learning, Moses used the I-Spy strategy to get students to find certain polygons on this poster.
I spy a shape that has 4 sides and 4 vertices.
Once up in front of the class, students were asked to show how they knew the shape had 4 sides and 4 vertices (tracing and pointing). Moses labelled the shape on the poster.
This process was repeated several times.
Part 2: Moses introduced the problem to the class. Using cut-outs of pattern blocks, he asked students to make a house. Students work in small groups at the make it centre.
Moses was looking how students combined different pattern blocks to form the new shape (house). His anecdotal notes were based on this.
Here are some samples of student work.
Most students were at this stage.
Some were beginning to combine certain shapes in an intentional way:
Then there's our friend Hans, who always thinks outside the box:
Part 3: Moses gathered students on the carpet and laid out all the student samples.
Students were asked to find two houses that were the same. Once a student found two samples, Moses asked them to explain how they are the same.
This student is explaining that they are the same because there's a hexagon between two triangles.
Students did not notice that shapes were combined together to form new shapes so Moses ended the lesson. He knows where his teaching needs to focus: get students to the shape composer stage.
This lesson is based on a three part lesson in the Guide to Effective Instruction in Mathematics K-3: Geometry. You can find the entire lesson and others at http://eworkshop.on.ca/.