After learning about the different types of angles, building them with Legos and measuring the tracings with protractors, we moved on to triangles and polygons. It's a pretty easy leap to take your Lego angles and add a third piece to make a triangle.
Easy in theory, yes, but in reality it can be difficult to find a third piece that is just the right size. Make sure you have as many pieces as you can scrounge out of those Lego bins for this activity, and remember you are looking for the shape inside the Lego, not around the perimeter. You would have a pretty wonky triangle if you tried to trace the outside, but look how nice they come out when you trace inside! We classified our triangles by sides ( equilateral, isosceles and scalene) and angles (right, acute and obtuse), then the kids traced examples of each in their math notebooks. You could also measure the angles of the triangles you traced with your protractor.
Break out those double row bricks for polygons, and of course you can use your single rows as well. The kids had fun combining different bricks to make some wild polygons. A polygon is a multi-sided two dimensional figure made up of three or more line segments, so you can really go to town with building these shapes. We started out with traditional shapes such as squares and rectangles, then moved on to more creative builds. Since these were rather large constructions, the kids drew their examples instead of tracing them.
The real challenge is coming up next time - circles!