Texas Instruments
Area of Circles
High schoolers explore circles. In this algebra/geometry lesson, students discover the formula for the area of a circle, as they investigate the ratio of the area of a circle to the radius^2.
Teach Engineering
Discovering Relationships Between Side Length and Area
Consider the relationship between side length and area as an input-output function. Scholars create input-output tables for the area of squares to determine an equation in the first installment of a three-part unit. Ditto for the area of...
Curated OER
Discovering Pi
Define terminology related to a circle. Practice accuracy in measuring and then create a spreadsheet based on data collected from solving for parts of a circle. Groups can have fun analyzing their data as it relates to Pi.
Curated OER
Parachutes, Circles and Pi...Oh My!
Students explore different size circles to discover the relationship between diameter and circumference. In this circles and Pi instructional activity, students construct simple parachutes using circle patterns of varying sizes. Students...
Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, students relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a circle.
Balanced Assessment
Egyptian Statue
Investigate the proportional relationships of length, area, and volume. Learners use the dimensions of rectangular prisms to create ratios and proportions. They compare the different ratios to solve more advanced problems.
Curated OER
Discovering Pi
Sixth graders discover Pi. For this discovering Pi lesson, 6th graders measure the diameter and circumference of various circular objects. Students record their measurements in a table. Students discuss how Pi relates...
Curated OER
Discovering Pi
Learners relate Pi to a circle. In this circles activity, students identify the different properties of two dimensional objects. They relate Pi to the circumference, diameter and area of a circle .
Texas Instraments
Angles in Circles
Teach your learners how to investigate the relationship between a central angle and an inscribed angle which subtend the same arc of a circle. The dynamic nature of Cabri Jr. provides opportunity for conjecture and verification.
Curated OER
Discovering Pi
Sixth graders measure circumference and diameter to the nearest eighth of an inch, record measurements on a spreadsheet, and use the internet to complete a "scavenger hunt" of facts concerning pi.
Curated OER
Scale Factor- Surface Area and Volume
Young scholars calculate the surface area and volume of shapes. For this geometry lesson, students create different scales and calculate the volume and area for each shape. They compare and contrast between the different scales and shapes.
Curated OER
Areas of Polygons
Students calculate the are of regular polygons. In this geometry lesson, students create polygons on the computer and move it around to create different shapes. They explore the area of different polygons and how they inter-relate.
Curated OER
Geometry and Geoboard
Sixth graders use geoboards and dot paper to experiment with geometric concepts. In this geometry lesson plan, 6th graders complete four activities using geoboards or dot paper including naming points on a coordinate plan and finding the...
Curated OER
Area Unit
Students solve the area for parallelograms,squares, rectangles, trapezoids, and triangles. In this geometry lesson, students compare and contrast two dimensional shapes and apply their properties to solving real life scenarios. This is a...
Curated OER
Finding the Area of Regular Polygons
Students analyze relationship between the increase in polygons sides and a circle. In this geometry lesson, students relate the size of the central angle of a polygon, to a circle. They compare the formula for the area of a polygon and a...
EngageNY
Ptolemy's Theorem
Everyone's heard of Pythagoras, but who's Ptolemy? Learners test Ptolemy's Theorem using a specific cyclic quadrilateral and a ruler in the 22nd installment of a 23-part module. They then work through a proof of the theorem.
Curated OER
Pi
Sixth graders read the book "Sir Cumference and Knights of the Round Table" to introduce them to the concept of Pi. As a class, they discover where Pi originated and define the terms circumference, radius and diameter. To end the...
Curated OER
Circle Packing
Students identify different parts and properties of circles. In this geometry lesson, students identify the radius, diameter, semicircle and inscribed angle of a circle. They identify the tangent lines to a circle.
Curated OER
Secants, Tangents and Arcs
Students identify chords and angles. For this geometry lesson, students calculate the length of the chords inside and outside of-the circle. They differentiate between tangent and secant lines.
Curated OER
Around and Around
Students create a spreadsheet to record information about circular objects. They measure and record information from a variety of objects. Students calculate the ratio of the circumference to the diameter of each object. They find the...
Curated OER
Segments Formed by Intersectiong Chords, Secants, and Tangents
Learners investigate the properties of segments formed which chords, secants, and tangents, intersect. The dynamic nature of Cabri Jr. allows high schoolers to form and verify conjectures regarding segment relationships.
Curated OER
Radian Measure
Young mathematicians identify central angles, arcs and radius of circles in this pre-calculus lesson. They identify the proportion of the circle based on its radius while they convert between degrees and radians measurements.
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
Getting to Know You
Students converse with each other while playing a game in order to discover things that are alike and things that are different about themselves. The students gather data about themselves, organize and display data on the graph, and...