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...

Learners explore intersecting lines. In this intersecting lines lesson, students investigate shapes consisting of parallel, perpendicular, and similar lines. Learners investigate these lines in shapes around them.

In this fraction lesson, students manipulate paper by folding it to create different shapes and sizes, they explore the concept of fractions, and discuss their observations as a class. This is a great lesson for getting students...

In addition to the catchy title, this lesson plan provides upper graders an opportunity to more closely scrutinize the attributes of plane figures. In particular, they focus on the similarity of different shapes. Both whole-class and...

Learners of all ages investigate area and perimeter through pentominoes. In this geometry lesson plan, young scholars calculate the are and perimeter of different geometric shapes and describe the properties of similar and congruent...

Young geometers investigate and apply properties of quadrilaterals.  After a review and discussion of key terms, learners use a computer applet to explore four-sided figures and classify them according to their attributes. The...

Building on young mathematicians' prior knowledge of three-sided shapes, this lesson plan series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...

It's all about lines when going around. Pupils graph the relationship between the length of a side of a square and its perimeter. Class members explain the origin in context of the side length and perimeter. They compare the graph to the...

Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...

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.  

Population density, it is not all that it is plotted to be. Pupils analyze a scatter plot of population versus area for some of the states in the US. The class members respond to eight questions about the graph, specific points and...

Students examine tessellations and their geometric properties. Students explore the concept of tessellations and lines, planes, angles, and polygons. Students experiment with the area and perimeter of polygons. Students analyze...

In this geometric figures worksheet, 10th graders solve and complete 11 different word problems. First, they find the area of a regular octagon with a given side. Then, students find the area of each shaded region. They also find the...

Fourth graders explore triangles. In this math lesson, 4th graders discuss the different types of triangles. Students create triangles using wiki sticks. Students complete an online matching game.

Geometry is everywhere, and I mean everywhere! Those skillful mathematicians discuss shapes and then come up with a well-researched list of shapes seen in everyday applications. They put their knowledge of shapes to work as each small...

Explore the concept of volume of prisms using an applet to perform the calculations. The link to the interactive applet is embedded into the lesson plan as well as a link to associated data sheets. Get your math class to the computer lab...

Students investigate ways to enhance an object's flying ability.  In this model construction lesson, students construct two paper airplanes, one of which is twice as big as the first.  Students compare and contrast the two...

Students participate in a unit on triangles. Through the unit they explore different way to make basic shapes using triangles. They also examine the basic properties of triangles and the relationships among basic geometrical shapes in...

Students investigate geometric shapes in their environment, make a geometric design, and write paragraphs describing the design.

Students use a monochromatic palate, select shades and tints for a selected hue, or select complimentary or analogous colors for a quilt design. They design quilt squares using basic geometric shapes, repetition, balance, and proportion.

Challenge your classes to design and market a new product. Collaborative groups use geometry skills to create packaging for their products. Finally, they plan a marketing strategy to present to a marketing specialist.

Tenth graders explore the properties of the incenter of a triangle. In this geometry lesson plan, 10th graders construct a triangle and the angle bisectors of each angle. The dynamic properties of Cabri Jr. allow students to locate and...

In this math worksheet, students describe the properties of various 3D shapes. Students tell about faces, edges and corners and name the geometric figures.

Young scholars explore two dimensional geometric figures. They explore the relationships and measurements of geometric figures. Students apply proportion and scaling. They design a city park for young scholars and teenagers.