Texas Instruments
Texas Instruments: Special Parallelograms
In this activity, students will study special types of parallelograms like rhombus and rectangle, and investigate properties related to their diagonals.
Wolfram Research
Wolfram Math World: Rhombus
This math site explains properties of the rhombus, gives a visual aid to help with the formula given for it's area.
ClassFlow
Class Flow: Quadrilaterals
[Free Registration/Login Required] This lesson goes deep into properties of parallelograms and special quadrilaterals. It has class interaction, student interaction, student practice, and whole class assessment.
Alabama Learning Exchange
Alex: Geometrica Fights Back!
This activity is designed to give students practice with the properties of special quadrilaterals (parallelograms, rectangles, rhombuses, squares, trapezoids, and kites). The students are provided with a "murder mystery" sheet with...