Students use a geoboard (or Geoboard App on iPad) to construct a PENTAGON using specific triangles and quadrilaterals. (Listed here)

right triangle isosceles triangle parallelogram trapezoid
acute triangle scalene triangle kite rectangle
obtuse triangle quadrilateral rhombus square

This product covers Common Core Standards in grades:
3rd- 3G1: Reason with Shapes and Attributes
4th-4.G.2: Classify two-dimensional figures
5th- 5.G.3-4: Classify two-dimensional figures into categories based on their properties.
6th- Review of 2-D figures