This activity has 16 cards including diagrams, perimeter, area formula, and area of two-dimensional figures. The two-dimensional figures include a triangle, parallelogram, trapezoid, and rhombus. Students will sort the cards according to which two-dimensional figure they belong to. This is a great activity for groups of 2-4 and can be laminated so that you can use it year after year. You could also have students glue it into their interactive notebooks.