Curated OER
Pythagorean Theorem by Graphic Manipulation
There are many different ways to show a proof of the Pythagorean Theorem.  Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
Shodor Education Foundation
Pythagorean Theorem
Most adults remember learning about the Pythagorean theorem, but they don't all remember how to use it. The emphasis here is on developing an intuitive understanding of how and when to use the theorem. Young mathematicians explore...
Mathematics Assessment Project
Sorting Equations of Circles 1
Round and round we go. Learners first complete a task on writing equations of circles. They then take part in a collaborative activity categorizing a set of equations for circles based on the radius and center.
EngageNY
Solve for Unknown Angles—Angles and Lines at a Point
How do you solve for an unknown angle? In this sixth installment of a 36-part series, young mathematicians use concepts learned in middle school geometry to set up and solve linear equations to find angle measures.
EngageNY
Exploiting the Connection to Trigonometry 2
The class checks to see if the formula for finding powers of a complex number works to find the roots too.  Pupils review the previous day's work and graph on the polar grid. The discussion leads the class to think about...
EngageNY
Linear Transformations Applied to Cubes
What do you get when you combine a matrix and a cube? Well that depends on the matrix! Pupils use online software to graph various transformations of a cube. Ultimately, they are able to describe the matrix that is responsible for a...
Noyce Foundation
Which is Bigger?
To take the longest path, go around—or was that go over? Class members measure scale drawings of a cylindrical vase to find the height and diameter. They calculate the actual height and circumference and determine which is larger.
 
Noyce Foundation
Boxes
Teach your class to think outside the box. Scholars use the concept of equality to solve a problem in the assessment task. They determine how to use a scale to identify the one box out of a set of nine boxes that is heavier than the others.
DiscoverE
Spaceship to Mars
Feel like a rocket scientist for the day. Using only paper and tape, scholars create a framework for a spaceship to Mars. Each sheet of paper costs $10 million and each piece of tape costs $100,000. Make sure you stay within budget! 
Curated OER
Tiling the Classroom
Students see how to identify regular polygons, how to slide, turn and flip polygons, and why certain polygons tessellate better than others. Groups create a one foot square design to be used to tile the classroom. Great lesson!
Texas Instruments
Drawing a Line Tangent to a Circle
Explore lines tangent to a circle. In this math lesson plan, students manipulate circles and lines on a TI calculator. They draw a circle  and analyze perpendicular lines intersecting the circle in only one place. This activity...
Curated OER
Sharing Brownies: Fractions That Represent a Fair Share
Elementary graders discover the concept of fractional pieces of a whole. They investigate the meanings of fractions in everyday life and why they are used. Pupils divide brownies amongst each other to demonstrate the use of fractions...
Curated OER
Design a Colonial Garden
Students explore botany by completing an art design activity in class. In this gardening history lesson, students identify the plants and crops utilized in the Colonial era for both food and medicine. Students utilize geometry to create...
Illustrative Mathematics
Points equidistant from two points in the plane
Young geometers apply their deductive reasoning skills and knowledge of proving triangles congruent in a task that asks them to prove if a point lies on the perpendicular bisector of a segment, then it is equidistant from the endpoints...
Achieve
Framing a House
If members of your class wonder where they can use the math they learn in middle school, let them discover the answer. Learners apply geometry concepts of scale and measure to calculate the costs of framing a house addition.
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...
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Mathematics Assessment Project
Deducting Relationships: Floodlight Shadows
Try to figure out what happens with shadows as a person moves between two light sources. A formative assessment lesson has individuals work on an assessment task based on similar triangles, then groups them based on their...
Inside Mathematics
Magic Squares
Prompt scholars to complete a magic square using only variables. Then they can attempt to solve a numerical magic square using algebra. 
EngageNY
Representing Reflections with Transformations
In the 16th lesson plan in the series of 32 the class uses the concept of complex multiplication to build a transformation in order to reflect across a given line in the complex plane. The lesson plan breaks the process of reflecting...
EngageNY
Exploiting the Connection to Trigonometry 1
Class members use the powers of multiplication in the 19th installment of the 32-part unit has individuals to utilize what they know about the multiplication of complex numbers to calculate the integral powers of a complex...
EngageNY
Coordinates of Points in Space
Combine vectors and matrices to describe transformations in space. Class members create visual representations of the addition of ordered pairs to discover the resulting parallelogram. They also examine the graphical representation...
Curated OER
Yummy Math
Young mathematicians use bags of Skittles to help them gain practice in graphing and organizing data. They work in pairs, and after they have counted and organized their Skittles, they access a computer program which allows them to print...
Curated OER
Countries Involved in World War II
Students create their own floor map of Europe, Northern Africa, and the Pacific. They locate, identify, and speak for one of the countries involved. In addition, they classify the country they represent as an Axis Power or as an Allied...