The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...

Four triangles are depicted for learners to construct on a geoboard. They compute and compare the areas, and so meet one of the sixth grade Common Core standards for geometry. Note that the set of triangles does not include a right...

Zero in on an interesting resource involving radar technology. Groups construct a radar sensing unit and learn to calibrate the system. Using the radar system and the Pythagorean Theorem, they calculate distances between objects.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

Find resources for class instruction on concurrence: a lesson on concurrence of medians, altitudes, angle bisectors, and perpendicular bisectors complete with definitions and example diagrams; a six-question practice quiz; and...

Learn how to construct the bisectors, median and altitude of a triangle.

This site contains a wealth of problems that deal with the basic definitions of medians, altitudes, angle bisectors, and perpendicular bisectors or the defining characteristics of the different types of triangles. There are also...

Could the altitude of the city hosting the Olympic and Paralympic Games have an effect on performance in the long jump? This challenging activity encourages mathematical reflection, investigation and discussion as students explore how...