A triangle, square, hexagon, and circle all have a perimeter of one unit. Eighth graders must attempt to find the area of each and arrange them in order from least to greatest areas. A terrific task for applying four different...

Pupils figure out how to be resourceful when tasked with finding the area of a triangle knowing nothing but its endpoints. Beginning by exploring and decomposing a triangle, learners find the perimeter and area of a triangle. They...

Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....

What? The calculation of area is a linear distance? A short video shows how to use the areas of simple polygons to estimate the area under a graph. Pupils divide the area under a curve into figures to easier calculate the area. Given...

Scholars learn how to determine the area of compound shapes by finding the areas of the basic shapes that make it up. Pupils find the areas by adding areas together or subtracting them.

Viewers learn how to apply proportional reasoning to find area of sectors and arc lengths with a video that starts off explaining how to find the areas of circle sectors and the lengths of arcs. Scholars then practice solving problems...

Scholars can use area formulas, but can they apply what they know about area? The lesson challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and other...

How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...

Find the area of triangles, rectangles, and parallelograms using this metric activity.

Unfortunately for young mathematicians, the world isn't made entirely of parallelograms, triangles, and trapezoids. After first learning the area formulas for these common shapes, students apply this new knowledge to...

Lateral area and surface area are simple concepts, but calculating them is not as easy! Using formulas, learners calculate lateral area and surface area for the same three-dimensional figures. The resource discusses the formula variables...

As they investigate scaling figures and calculate the resulting areas, groups determine the area of similar figures. They continue to investigate the results when the vertical and horizontal scales are not equal. 

Imagine a world built of triangles. A performance task asks scholars to consider just that. They use their knowledge of special segments of a triangle to make decisions about the area of triangular plots of land.

Not all structures take the shape of a polygon. The 21st lesson in a series of 29 shows young mathematicians they can create polygons out of composite shapes. Once they deconstruct the structures, they find the area of the composite figure.

You'd be surprised what you can do with a string! The constraint is the length of string, and the task is to maximize area. Given a series of composite shapes, learners must create a formula for the maximum area for a specified...

It's a piece of pizza! Pupils learn about a sector of a circle as a slice of the circle and determine how to find its area. Scholars continue to find out how to calculate the segment of a circle based on the sector's area. At the end,...

When algebra and geometry get together, good things happen! Given a system of inequalities that create a quadrilateral, learners graph and find vertices. They then use the vertices and Green's Theorem to find the area and perimeter of...

Surface area is the sum of the parts. Given the measurements of different prisms, pupils determine their surface areas. Individuals find the area of each surface and figure out the surface area by finding the sum. The video, part of a...

Our teacher told us the formula had one-third, but why? Using manipulatives, classmates try to explain the volume formula for a pyramid. After constructing a cube with six congruent pyramids, pupils use scaling principles from...

Learners discover how to find missing sides and angles using trigonometry. Scholars first watch a video covering the Law of Sines and Cosines, as well as the area formula for a triangle. To test their knowledge, they complete a worksheet...

Determine the level of understanding within your classes using a summative assessment. As the final lesson in a 29-part module, the goal is to assess the topics addressed during the unit. Concepts range from linear angle relationships,...

Your visual geometry learners will appreciate triangle drawings as they model the triangle sum theorem and algebraically solve to find the missing interior angle in a triangle. Practice problems increase in complexity and vary in their...

In this area of polygons activity, 9th graders solve two area of rectangles, one area of parallelogram, and ten area of triangles problems.  The formulas for finding the area of these figures are provided.

Find the area as it slides. Pupils derive an equation to find the painted area of a section of a trapezoidal-shaped stage The section depends upon the sliding distance the edge of the painted section is from a vertex of the trapezoid....