National Council of Teachers of Mathematics
Perplexing Parallelograms
In this geometry worksheet, young mathematicians divide a parallelogram into four, by choosing points along a diagonal. Students calculate the area of each parallelogram and look for any patterns that may emerge. The one-page...
Curated OER
Patch Tool
Students use an Internet tool to explore shapes and how they combine. In this patterns instructional activity, students create quilting patterns using various shapes. Students recognize how the shapes fit together.
National Council of Teachers of Mathematics
Nctm: Illuminations: Igd: Area of a Parallelogram
Use this interactive tool to learn how to find the area of a parallelogram. Click on "Instructions" for details on how to use this tool. Click on "Explore" for more ideas.
National Council of Teachers of Mathematics
Nctm: Illuminations: Igd: Area of a Parallelogram
This applet will show you how to divide the parallelogram into pieces, arrange them together to form a rectangle, and then use the formula for the area of a rectangle to find the area of the parallelogram.
National Council of Teachers of Mathematics
Nctm: Illuminations: Area of Triangles
To find the area of a triangle, try to make a parallelogram using a copy of the triangle.
National Council of Teachers of Mathematics
Nctm: Illuminations: Shape Cutter
This computer tool allows students to compose and decompose shapes by making cuts and rearranging the pieces. The tool has an exploration section for learning exercises.