Classifying figures by features is a fundamental geometry skill. Use this lesson plan to teach your students how to categorize triangles by internal angle types.

In this lesson your students will classify two-dimensional shapes using a Venn diagram based on their features.

You'll see angles from every angle! Students will describe and compare different angles they see in everyday situations. Use this lesson on its own or use it as support to the lesson Classifying Triangles by Internal Angles.

So many students love to read books in a series but they don't give much thought to what a series really is. In this lesson students discover the two kinds of book series and apply classifying criteria to examples in the library.