Triangles Websites


Virtual Pinboard There is so much to do here! This Geoboard allows one to create shapes with any number of vertices, color the shapes, measure with a ruler or protractor, add labels to any part of the drawing, and you can even print your creation. Use may use centimeter paper, or a triangular grid as your background. This is a must see!


Exploring and Solving Triangles LearnAlberta has some outstanding content related to Geometry. This lesson has interactive problems to solve the angles in a triangle. There is also a video, and a 4 page worksheet with the problems presented on the website.

Shapes in Space There are 4 levels of increasing difficulty in this game. Students identify 2D and 3D shapes, discriminate polygons from non-polygons, and attributes such as edges, sides, faces, and vertices. Very colorful with lots of sound effects, and even a arcade game-like bonus round.


Exploring Similarity and Congruence Students can drag, flip, rotate, and resize pairs of triangles to determine if they are congruent or similar. Like the other lessons from LearnAlberta, this one has a short video and a printable worksheet.

Enlargements On the first level a variety of shapes and objects are displayed in two different sizes. By manipulating the size of the grid, students are able to determine the scale factor by which the object was either enlarged or reduced. The second level presents students with a shape that they must enlarge to a given scale. This "flexigon" has vertices that may be dragged in any direction. There are also worksheets for each activity.