Virginia Department of Education
Angles in Polygons
Polygons — it's all about the angles. Groups work with dynamic geometry software to find the sum of the measures of the angles of various polygons. After finding the information for several polygons, the groups generate a formula that...
Curated OER
Getting It Right! An Investigation of the Pythagorean Theorem
Learners construct a variety of right triangles using a right-angled set square, cutting corners from pieces of paper or cardboard, and using dynamic geometry software. They measure the sides of these various right triangles and record...
Radford University
Building a House
Ever dream of becoming an architect? Here's your chance to give it a try. After reviewing facts about triangles and quadrilaterals, pupils learn about the basics of architecture by talking to an architect or housing expert. They use...
Curated OER
GEOMETRY UNIT
Students, through investigation facilitated by dynamic geometry software, determine geometric properties and relationships involving two-dimensional shapes, and apply the results to solving problems.
Virginia Department of Education
Angles, Arcs, and Segments in Circles
Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...
Virginia Department of Education
Properties of Quadrilaterals
What type of quadrilateral is that? Discover the difference between the types of quadrilaterals. Small groups investigate types of quadrilaterals using geometry software to find their properties. To keep track of the different...
02 x 02 Worksheets
Symmetry
Get learners' minds rotating and reflecting while looking for symmetry. Pupils investigate figures to determine the number of lines of symmetry and if the figure has rotational symmetry. Classmates work together in groups to find out the...
Curated OER
Geometry, Measurement & Reasoning
Learners complete worksheets involving rotational symmetry. In this geometry lesson, students complete worksheets to identify rotational symmetry and rotations. They compare and contrast rotated figures. Learners examine the relationship...
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...
Concord Consortium
Shooting Arrows through a Hoop
The slope makes a difference. Given an equation of a circle and point, scholars determine the relationship of the slope of a line through the point and the number of intersections with the circle. After graphing the relationship, pupils...
Virginia Department of Education
Similar Triangles
Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...
Curated OER
Inscribing a Circle in a Triangle
Pupils investigate inscribing a circle in a triangle. They use Cabri Jr. to draw a triangle, locate the incenter, and use the distance from the incenter to a side of the triangle to inscribe a circle. The dynamic nature of the geometry...
Curated OER
Fractal and the Dragon Curve
Students explore Fractal designs. In this geometry lesson, students observe the different polygons created in nature and relate it to math. They define polygons on planes and rotate polygons about a point.
EngageNY
Parallel and Perpendicular Lines
Use what you know about parallel and perpendicular lines to write equations! Learners take an equation of a line and write an equation of a line that is parallel or perpendicular using slope criteria. They then solve problems to...
EngageNY
Modeling Video Game Motion with Matrices 2
The second day of a two-part lesson on motion introduces the class to circular motion. Pupils learn how to incorporate a time parameter into the rotational matrix transformations they already know. The 24th installment in the 32-part...
Curated OER
Area of Circles and Probability
Students investigate the area of squares and circles. In this geometry lesson, students calculate the area and probability of simple events. They work on a laptop using Safari.
Curated OER
Pythagorean Theorem: Triangles and Their Sides
Students investigate triangles and their relationship to each other. In this geometry lesson, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and oblique...
Curated OER
The Dragon Curve Fractal
Learners identify the properties of a dragon curve. In this geometry instructional activity, students identify sequences and patterns as they solve fractals. They investigate patterns found in nature.
Curated OER
Geogebra Basics
Students identify basic geometric shapes using Geogebra. In this geometry instructional activity, students work on a laptop as they explore different geometric shapes. They calculate the area and perimeter of triangles.
Curated OER
Exploring the Centroid of a Triangle
Pupils examine the centroid of a triangle as they use Cabri Jr. to construct a triangle and its medians. The dynamic nature of the software allows learners to measure the lengths of the segments in the triangle and conjecture and verify...
Curated OER
Investigating Lengths of Segments in a Triangle
Pupils explore the midsegment of a triangle in the geometry lesson. They draw and measure the segment joining the midpoints of the two sides of a triangle and compare its length to the length of the third side of the triangle. The...
Curated OER
Perpendicular Bisector of a Line Segment
High Schoolers investigate the perpendicular bisector of a line segment. They use Cabri Jr. to construct the perpendicular bisector of a segment. The dynamics capabilities of Cabri Jr. allow your learners to observe the lengths of 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
Altitude, Median, and Angle Bisector of a Triangle
Learners investigate the special properties of an altitude, a median, and an angle bisector and explore how these special segments divide the area of a triangle. The dynamic nature of Cabri Jr. allows pupils to form and verify conjectures.