Key Curriculum Press
Properties of Special Parallelograms
Rhombuses, rectangles and squares are have special properties. In this lesson plan, young geometers investigate and make conjectures about diagonals, angles, and parallel lines of parallelograms.
CK-12 Foundation
Ck 12: Elem Math: Identifying the Properties of Rectangles
[Free Registration/Login may be required to access all resource tools.] Students watch a video tutorial and attempt practice problems on identifying the properties of rectangles.
University of Cambridge
University of Cambridge: Nrich: Is a Square a Rectangle?
This one page website offers a challenge working with rectangles that can lead to a discussion of their properties. Teacher notes offer direction and a solution is offered at this website.
University of Cambridge
University of Cambridge: Nrich: Making Squares
On this one page website sharpen your logic, spatial sense, and pattern recognition skills while working on this challenge. The solution is available to double check your solution.