Illustrative Mathematics
3-D Shape Sort
From the apple on your desk and the coffee cup in your hand, to the cabinets along the classroom wall, basic three-dimensional shapes are found everywhere in the world around us. Introduce young mathematicians to the these common figures...
Illustrative Mathematics
Overlapping Rectangle
Challenge young mathematicians' ability to compose and decompose shapes with this fun geometry puzzle. The goal is simple, locate all of the rectangles shown in a picture of three overlapping rectangles. Perform this activity as a whole...
Illustrative Mathematics
Grandfather Tang's Story
It's amazing the complex figures that can be made using only a few simple shapes. Following a class reading of the children's book Grandfather Tang's Story by Ann Tompert, young mathematicians use sets of tangrams to create models of the...
Illustrative Mathematics
Counting Squares
Challenge young mathematicians' understanding of squares with this geometry puzzle. The task is simple, identify as many squares as possible in a 3x3 array. Allow learners to work independently or in pairs as they search for squares,...
Curated OER
Tile Patterns I: Octagons and Squares
This can be used as a critical thinking exercise in congruence or as a teaching tool when first introducing the concept. Four octagons are arranged in such a way that a square is formed in the middle. With this information, geometry...
Illustrative Mathematics
Stained Glass
A complex question looking for the total cost of a stained glass window by calculating area and circumference of a circle. With detailed components, this activity will challenge your designers to figure out if they have enough money to...
Illustrative Mathematics
Why Does SSS Work?
While it may seem incredibly obvious to the geometry student that congruent sides make congruent triangles, the proving of this by definition actually takes a bit of work. This exercise steps the class through this kind of proof by...
Mrs. Burke's Math Page
The Amazing Pi Race
Add a sense of excitement to your math class with this race across the country. Using their knowledge of all things circular, young mathematicians work in pairs answering a series of pi-related word problems as they hop from one city to...
Illustrative Mathematics
Toilet Roll
Potty humor is always a big hit with the school-age crowd, and potty algebra takes this topic to a whole new level. Here the class develops a model that connects the dimensions (radii, paper thickness, and length of paper) of a common...
Illustrative Mathematics
Hexagonal Pattern of Beehives
Young geometers and biologists investigate the math of nature in an activity that is just the bee's knees. Participants will study the tessellations of hexagons in a beehive, along with the natural rationale behind the specific shape....
Curated OER
Finding the Area of an Equilateral Triangle
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...
Illustrative Mathematics
Running Around a Track I
The accuracy required by the design and measurement of an Olympic running track will surprise track stars and couch potatoes alike. Given a short introduction, the class then scaffolds into a detailed analysis of the exact nature of the...
Curated OER
Tile Patterns II: Hexagons
After learning that the sum of interior angles for triangles is 108 degrees, take it further to show that the sum of angles in any polygon is the same! Using hexagons, pupils practice finding the measure of the six congruent angles. Make...