Streets, bridges, and intersections, oh my! Parallel lines and transversals are a present in the world around us. Learners begin by discovering the relationship of the angles formed by parallel lines and a transversal. They then...

Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...

Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...

Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...

Create the ultimate miniature golf course. The 93-page model curriculum unit from the Massachusetts Department of Elementary and Secondary Education contains nine lessons on understanding similarity in terms of both Euclidean geometry...

Given conjectures about circles, the student will use deductive reasoning and counterexamples to prove or disprove the conjectures.

[Free Registration/Login may be required to access all resource tools.] In this lesson students prove two triangles are congruent with the Angle-Side-Angle and Angle-Angle-Side shortcuts. Students examine guided notes, review guided...

[Free Registration/Login may be required to access all resource tools.] Prove two triangles are congruent with the Side-Angle-Side shortcut.

[Free Registration/Login may be required to access all resource tools.] This concept introduces students to the SAS Triangle Postulate and how to prove that two triangles are congruent given only information about two pairs of sides and...

MathWorld provides the definition of a rectangle and the area formula of a rectangle.