Illustrative Mathematics
Illustrative Mathematics: 8.g Circle Sandwich
Eighth graders are presented with a drawing of a large square inscribed by a circle which is itself inscribed by a second square. They are asked to find the area of the circle outside the smaller square and compare it to the area of the...
Purple Math
Purplemath: Matrix Inversion: Finding the Inverse of a Matrix
Inverse matrices are very useful for solving matrix equations. But, given a matrix, how do you invert it? How do you find the inverse? The technique for inverting matrices is kind of clever. For a given matrix A and its inverse A-1, we...
Better Lesson
Better Lesson: Partitioning Rectangles and Squares
This site provides six practice activities to learn how to partition a rectangle into rows and columns of same-size squares and count to find the total number of them.
CK-12 Foundation
Ck 12: Elem Math: Identifying Rectangles, Squares, Circles, and Triangles
[Free Registration/Login may be required to access all resource tools.] The video discusses a brief overview of circles, rectangles, squares, and triangles and helps students determine which shape is shown and why. The video is followed...
CK-12 Foundation
Ck 12: Geometry: Quadrilateral Classification
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to classify quadrilaterals in the coordinate plane.
CK-12 Foundation
Ck 12: Algebra: Pythagorean Theorem and Its Converse
[Free Registration/Login may be required to access all resource tools.] Recognize and use the Pythagorean Theorem
CK-12 Foundation
Ck 12: Geometry: Quadrilateral Classification
[Free Registration/Login may be required to access all resource tools.] Recognize and classify quadrilaterals
BBC
Bbc: Bitesize: Maths: 2 D Shapes
Learn about the properties of 2-D shapes: circles, triangles, polygons, and quadrilaterals. Includes information, video, and examples about each, with games and quizzes for reinforcement.
Alabama Learning Exchange
Alex: "Tan"
The Chinese character mark formerly known as "Tan" is the first of two lessons to introduce first grade students to geometry using tangrams. This instructional activity incorporates history, math, and language arts. In this instructional...
Math Open Reference
Math Open Reference: Square
A complete reference guide to the square. It provides definitions, attributes, and interactive activities that enhance further explanation. Includes links to related topics.
Geometry Help
Geometry Help: Squares
Explains the basic concept of a square with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
CK-12 Foundation
Ck 12: 2.6 Solving Radical Equations
This section explores the process for solving radical equations, including those with square, third, and fourth roots. It also investigates how, when, and why some solutions that appear to be correct are incorrect, and are therefore...
Quia
Ixl Learning: Types of Quadrilaterals
Brush up on your math skills relating to the types of quadrilaterals then try some practice problems to test your understanding.
Quia
Ixl Learning: Squares
Brush up on your math skills relating to squares then try some practice problems to test your understanding.
Quia
Ixl Learning: Parallelograms
Brush up on your math skills pertaining to parallelograms then try some practice problems to test your understanding.
National Council of Teachers of Mathematics
Nctm: Illuminations: Proof Without Words: Completing the Square
Use this interactive geometric proof to complete the square using geometry.
PBS
Pbs Learning Media: Shapes: Peg + Cat
We are learning about how shape attributes helps us to see how shapes are alike and different. This site provides four resources for shapes including 3-D.
PBS
Pbs Learning Media: Math + Arts: Geometric Quilts
In this lesson, students will create a class quilt of nine patch paper quilt blocks using geometry.
Better Lesson
Better Lesson: Equivalent Numerical Expressions, Day 2 of 2
How can you represent the area of a diagram using numerical expressions? Students connect their knowledge of area and equivalent expressions to the commutative and distributive properties for day 2 of this investigation.
Better Lesson
Better Lesson: Equivalent Numerical Expressions, Day 1 of 2
How can you represent the area of a diagram using numerical expressions? Students apply their knowledge of area and order of operations to match area diagrams with numerical expressions.
Other
Nearpod: 2 D Shapes
In this lesson on 2D shapes, 3rd graders will learn to discriminate quadrilaterals from other polygons. Additionally, they will be able to identify attributes of a square, rectangle, and rhombus.
Harvey Mudd College
Mudd Math Fun Facts: Squares Ending in 5
This math tutorial features an exercise in which you are given any two-digit number that ends in 5 and then square it in your head.
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Polyhedrons
This in-depth paper examines the idea of convexity. Euclid's Elements, the first geometry textbook, assumed convexity without mentioning the term.
History is Fun
Jan Brett: Geometric Shapes Flashcards Pdf
Print out these colorfully illustrated PDF file pages to practice learning your basic two dimensional geometric shapes. Fold them in half and one side shows the shape while the other side shows the shape with the correct name. Put them...