This short video and interactive assessment activity is designed to give fourth graders an overview of triangle classifications.

The purpose of this task is to provide students an opportunity to use mathematics addressed in different standards in the same problem.

This high level task is an example of applying geometric methods to solve design problems and satisfy physical constraints. This task is accessible to all students. In this task, a typographic grid system serves as the background for a standard paper clip.

In this unit, students investigate fractional parts of the whole and use translations, reflections, rotations, and line symmetry to make four-part quilt squares. Students have a practical context for using the mathematical terms associated with divisions of the square, transformations, and symmetries. Suggestions for implementation and extensions are included.

Students act as civil engineers developing safe railways as a way to strengthen their understanding of parallel and intersecting lines. Using pieces of yarn to visually represent line segments, students lay down "train tracks" on a carpeted floor, and make guesses as to whether these segments are arranged in parallel or non-parallel fashion. Students then test their tracks by running two LEGO® MINDSTORMS® NXT robots to observe the consequences of their track designs, and make safety improvements. Robots on intersecting courses face imminent collision, while robots on parallel courses travel safely.

This short video and interactive assessment activity is designed to teach fourth graders about partitioning composite figures into rectangles to find area 1.

This interactive applet lets students create quilting type patterns and explore tessellation possibilities. The applet gives learners a choice of six polygons that can be turned or flipped and fitted together. Suggestions for exploration and five challenge patterns are provided. The tool supports a number of lessons and units including What's So Special About Triangles and Virtual Pattern Blocks (cataloged separately).

This five lesson Illuminations unit gives students an opportunity to create and analyze numeric and geometric patterns with particular emphasis on growing patterns. The lesson titles are respectively, What's Next?, Patterns On Charts, Growing Patterns, Exploring Other Number Patterns and Looking Back And Moving Forward. Each lesson includes learning objectives, material list, instructional plan, linked resources and assessment options.

The objective of this lesson is to illustrate how a common everyday experience (such as playing pool) can often provide a learning moment. In the example chosen, we use the game of pool to help explain some key concepts of physics. One of these concepts is the conservation of linear momentum since conservation laws play an extremely important role in many aspects of physics. The idea that a certain property of a system is maintained before and after something happens is quite central to many principles in physics and in the pool example, we concentrate on the conservation of linear momentum. The latter half of the video looks at angular momentum and friction, examining why certain objects roll, as opposed to slide. We do this by looking at how striking a ball with a cue stick at different locations produces different effects.

"Each student creates parallelograms from square sheets of paper and connects them to form an octagon. During the construction, students consider angle measures, segment lengths, and areas in terms of the original square" (from NCTM's Illuminations).

This task can be implemented in a variety of ways. For a class with previous exposure to properties of perpendicular bisectors, part (a) could be a quick exercise in geometric constructions, and an application of the result. Alternatively, this could be part of an introduction to perpendicular bisectors, culminating in a full proof that the three perpendicular bisectors are concurrent at the circumcenter of the triangle, an essentially complete proof of which is found in the solution below.

In this interactive Flash game learners use their knowledge of coordinates on a grid to move Plotter the penguin and avoid trouble. The game includes three levels of difficulty, a story mode, and a choice of five different games to play. Each game provides instruction as well as in-depth help in linked PDF documents.

This task is part of a series presenting important foundational geometric results and constructions which are fundamental for more elaborate arguments. They are presented without a real world context so as to see the important hypotheses and logical steps involved as clearly as possible.

In this lesson, students classify polygons according to more than one property at a time. As they play the game, they are motivated to examine relationships among geometric properties. Another purpose of the game is to give students a format for using important geometric vocabulary. All game instructions and models for playing pieces are included here.

In this math activity, learners classify polygons according to more than one property at a time. In the context of a game, learners move from a simple description of shapes to an analysis of how properties are related. This lesson guide includes sample steps in the game and extensions.

This short video and interactive assessment activity is designed to teach third graders about predicting the next shape in a sequence of 2d and 3d shapes.

This short video and interactive assessment activity is designed to teach second graders about predicting the next shape in a sequence of 2d and 3d shapes.

This short video and interactive assessment activity is designed to teach fourth graders about predicting the next shape in a sequence of 2d and 3d shapes.

This short video and interactive assessment activity is designed to teach fourth graders about predicting the next shape in a sequence of complex shapes.

This short video and interactive assessment activity is designed to teach third graders about predicting the next shape in a sequence of complex shapes.