EngageNY
One-Step Problems in the Real World
Mirror, mirror on the wall, which is the fairest resource of them all? Individuals write and solve one-step equations for problems about angle measurement, including those involving mirrors. Both mathematical and real-world problems are...
EngageNY
An Area Formula for Triangles
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
Improving Measurement and Geometry in Elementary Schools
The Sum of the Interior Angles of a Polygon
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this lesson.
Scholastic
Study Jams! Light Absorption, Reflection, & Refraction
Zoe and RJ are trying to photograph an egret on a lake, but they are having trouble with the lighting. Reflection, refraction, and absorption are explored through their thoughtful dialogue so that your physical scientists are illuminated...
Curated OER
Pattern Blocks
First graders examine a bag full of standard pattern blocks in the following shapes: triangle, hexagon, small rhombus, large rhombus (parallelogram), square, and trapezoid. They discuss the similarities and differences among them, count...
Curated OER
Property Lists for Quadrilaterals
Students establish classifications of shapes by various properties (angles, sides, etc.). They introduce the important properties of common shapes. Students develop an awareness of the wide variety of ways the 2-D shapes can be alike.
Mathematics Assessment Project
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve their...
Mathematics Vision Project
Module 6: Trigonometric Functions
Create trigonometric functions from circles. The first lesson of the module begins by finding coordinates along a circular path created by a Ferris Wheel. As the lessons progress, pupils graph trigonometric functions and relate them to...
Ohio Department of Education
Describing and Creating Plane Figures - Grade One
Young mathematicians draw, create, and describe different shapes using triangles. They discuss attributes of the original and created shapes. Pupils classify the created shapes and draw and write in mathematics journals to communicate...
Curated OER
Making and Describing Shapes
Explore the concept of creating and describing 2D and 3D shapes. Using geometry your scholars will describe the attributes of shapes and their properties. They explore and discover what happens when you combine shapes and then take...
Curated OER
THE FARMER CARES FOR THE LAND
Young scholars will identify cause and effect relationships in issues relating to Agriculture and the environment.Ask students to describe what farmers do. Then ask young scholars to define the word "environmentalist." Ask students if...
Curated OER
Area of irregular Polygons: Historical Motivator - Lewis and Clark Adventure
Seventh graders find the area of irregular polygons. For this lesson on calculating area, 7th graders use the adventures of Lewis and Clark as motivation to learn how to calculate the area of irregular polygons.