Lesson Plan
Curated OER

Angles and Arcs

For Teachers 9th - 10th
Students discuss the sum of central angles and use string to create them on circles. They find the measure and length of both minor and major arcs. Students give examples of concentric, similar, and congruent circles and congruent arcs.
Lesson Plan
Curated OER

Measuring Angles & Segments

For Teachers 10th - 12th
Students view a PowerPoint for a warm-up lesson. They practice measuring around the classroom, measuring such things as the length and width of a desk, pencil, door, and book. Students use a website to practice measuring angles.
Lesson Plan
Curated OER

Triangle Inequality Theorems Investigation

For Teachers 9th - 10th
Young scholars estimate and measure triangles. In this geometry lesson, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.