Students explore the relationships among the lengths, areas, and volumes of similar solids. They also discover what effect doubling the dimensions of a figure has on the resulting area.

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...

While the lesson focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can they...

Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...

In this adding worksheet, students draw three more of the geometric shapes shown in each row and write the total numbers. Students solve three problems.

Use this activity on cross-sections of three-dimensional shapes in your math class to work on algebra or geometry Common Core standards. The lesson includes a list of relevent terminology, and a step-by-step process to illustrate the...

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...

What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...

Geometers explore the concept of tessellations. They use a tessellation applet to manipulate shapes and design their own tessellation using the applet.

What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.

In this geometry worksheet, 10th graders use the theorems regarding right triangles to find the missing length in a special right triangle. The one page worksheet contains eleven questions. Answers are included.

Is the amount of information getting overwhelming for your geometry classes? Use this strategy as a way to organize information. The resource provides a handout of information studied in relation to triangle congruence. It includes a...

Learners examine the process of drawing a picture to scale. They analyze and discuss real-life blueprints for a house, and create a scale drawing of an original invention using calculators and rulers.

Tenth graders investigate the history of Pi and how it relates to circles. In this geometry lesson, 10th graders measure the circumference of a circle and the diameter of a circle. They relate these measurements to the number of Pi or 3.14

We know theorems about circles—now what? Class members prove a theorem, with half the class taking the case where a point is inside the circle and half the class taking the case where a point is outside the circle. The lesson then...

Second graders practice vocabulary related to measurement, mathematics, and dinosaurs. Using the engaging topic of dinosaurs, learners will calculate various information about dinosaurs and use measurement vocabulary. They will also...

Compare and classify 2-D shapes! Kindergarteners inspect the attributes of plane shapes and examine shapes in everyday life. They label the circles, squares, rectangles, and triangles they find. This is the website where you can find the...

Let your use of the resource be in proportion to its usefulness. Pupils investigate similar triangles by measuring side lengths and considering given angle measures. The results of the investigation help develop generalizations about...

Planning a party of 45 guests may be more complicated than it would seem.  Learners must design the space in accordance with these constraints about the space available in the room. They need to calculate area, circumference,...

Students perform transformations and translations using polygons. In this geometry lesson, students perform transformations on a coordinate plane. They identify the image and pre-image of each figure.

Students find the length of the arc of a circle. In this geometry lesson, students calculate the length of an arc and find the measure of the central angle given the length of the arc. They convert between linear and angular speed. They...

Have fun calculating angles for different polygons. The class differentiate the relationship between the interior and exterior angles of polygons. They discuss linear pair as it related the polygons and their angles. This is done as they...

In this solar storms instructional activity, students use a diagram given the location of two STEREO spacecraft satellites, a coronal mass ejection, the sun and the Earth to solve 2 problems about the coronal mass ejection. Students use...

In this geometry instructional activity, 10th graders determine the measures of various angle pairs:  supplementary, complementary, and vertical angles.  The two page instructional activity contains a combination of twelve...