Curated OER
Super Shapes Part 2 - Circles
Through the use of Internet, video, and hands-on activities, youngsters learn the parts and characteristics of a circle. This fantastic lesson has some excellent website activities included in the plan. Your kids will have a much greater...
EngageNY
Real-World Area Problems
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.
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Curated OER
Volume and Surface Area
Students explore volume and surface area. In this math lesson, students fill boxes with cubes to identify the volume of the boxes. Students discuss area.
Curated OER
Circumscribing a Circle About a Triangle
Pupils circumscribe a circle about a triangle. They construct a triangle using Cabri Jr and then circumscribe it. They then use knowledge of perpendicular bisectors and circumcenters to locate the center of the circle and then...
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Balanced Assessment
Triangle in Circle
Even kindergartners can draw triangles in circles, but the assessment task requires a bit more geometric knowledge. Scholars investigate triangles that have a diameter of a circle as one of its sides. They must consider triangles that...
Curated OER
Inscribing a Hexagon in a Circle
This activity is a follow-on activity to inscribing a square in a circle. The overall problem is more complex. It deals with geometric constructions, properties of triangles, and regular hexagons. The final part of the activity...
Curated OER
Triangle Inequality Theorem
High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...
Curated OER
Exploring the Circumcenter of a Triangle
Students construct the circumcenter of a triangle. In this constructing the circumcenter of a triangle lesson, students construct a triangle using Cabri Jr. Students draw perpendicular bisectors of the sides of the triangle. Students...
Curated OER
Exploring the Orthocenter of a Triangle
Young mathematicians explore the concept of triangles as they construct altitudes of triangles to find the orthocenter. Learners construct their triangles using Cabri Jr. on their graphing calculators and find that the altitudes of a...
Curated OER
Principles of Square Roots Lesson Plan
Middle and high schoolers investigate all the different places in math that square root is present. In this geometry lesson, pupils discuss square roots as it relates to a right triangle and construction. They go over altitude, rise,...
Curated OER
Area of Triangle using the Semi-Perimeter and Radius
Students investigate the properties of circles. For this geometry lesson, students calculate the area and perimeter of a triangle. They identify the perimeter and radius length of a circle.
Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, high schoolers relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a...
Curated OER
Equation of a Circle
Young scholars write the equation of a circle. In this geometry instructional activity, students check the solution of a coordinate pair by evaluating them. They graph the circle given the equation and radius.
Curated OER
Properties of the Centers of a Triangle
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This instructional activity requires the use of Cabri, Jr.
Curated OER
Ara of Circles
Students identify the differentiate the different properties of circles and parallelograms. In this geometry lesson, students calculate the area of each solid and identify the formula. They relate Pi to the circumference of a circle.
Curated OER
Surface Area with Polydrons
Students explore measurements by analyzing geometric shapes. In this surface area lesson plan, students identify the terms volume, weight, perimeter and area in order to find the requested measurements of specific polygons. Students...
Curated OER
Fill and Wrap It Up
Students find the surface area and volume of the solid figures by measuring the length and the height of each face and base. They use concrete models to derive formulas for finding perimeter, circumference, area, surface area, and volume...
Curated OER
Triangles with Collinear Circumcenters
Students identify the circumcenter of a triangle. In this geometry lesson, students construct a perpendicular bisector using a straight edge and a compass. They differentiate between triangles and collinear points.
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts...
Curated OER
Areas of Polygons
Learners calculate the are of regular polygons. In this geometry instructional activity, students create polygons on the computer and move it around to create different shapes. They explore the area of different polygons and how they...
Curated OER
Areas and Volumes
Tenth graders calculate the area and the volumes of polygons. In this geometry lesson, 10th graders review the formulas used to solve for the area and volume and explain to the class how they arrived at their answer. They search online...
Curated OER
Geometry and Geoboard
Sixth graders use geoboards and dot paper to experiment with geometric concepts. In this geometry lesson, 6th graders complete four activities using geoboards or dot paper including naming points on a coordinate plan and finding the area...