Curated OER
Travel Triangles
Students demonstrate and understanding of the three types of angles using triangles and quadrilaterals. In this angles lesson plan, students learn about acute, obtuse and right angles. They use cut-outs to find the areas of triangles and...
Curated OER
Measuring the Earth
High schoolers use principles of geometry to measure the circumference of the Earth. In this applied geometry lesson plan, students use mathematics to determine scientific information. They make measurements, calculate the central angle,...
Curated OER
Solve Word Problems with Geometry
In this geometry instructional activity, students solve word problems having to do with lines, angles, shapes, area, perimeter, and more. Students complete 57 problems total.
Curated OER
Angles: Greater Than, Less Than or Equal To 90 Degrees?
In this angles worksheet, students check the correct box, identifying angles as either greater than, less than or equal to 90 degrees. A reference web site is given for additional activities.
Virginia Department of Education
Constructions
Pupils learn the steps for basic constructions using a straightedge, a compass, and a pencil. Pairs develop the skills to copy a segment and an angle, bisect a segment and an angle, and construct parallel and perpendicular lines.
Illustrative Mathematics
Bank Shot
Young geometers become pool sharks in this analysis of the angles and lengths of a trick shot. By using angles of incidence and reflection to develop similar triangles, learners plan the exact placement of balls to make the shot....
EngageNY
Looking More Carefully at Parallel Lines
Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...
Houghton Mifflin Harcourt
Unit 6 Math Vocabulary Cards (Grade 5)
Acute angles, nets, and vertices are only a few terms that a set of flash cards includes. Among the 108 cards, two types are available; word cards printed in bold-faced lettering, and corresponding definition cards equipped with an...
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
EngageNY
Cyclic Quadrilaterals
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.
Mathematics Assessment Project
Floor Pattern
You'll never look at floor tiles the same again. An assessment task prompts learners to investigate relationships between patterns involving squares and kites to determine angle measurements. They then prove whether a given quadrilateral...
Curated OER
Positive and Negative Angles and Arcs
To better understand that the intersection point of two lines lies inside a circle, learners use their keen measurement skills. They discuss arcs, rays, tangent lines, and reflex angles. Then, they put their skills to work as they...
Curated OER
Geometric Shapes and Angles
In this geometry worksheet, 10th graders review polygons and solve for the missing angles of trapezoids and isosceles triangles. There are 10 questions on this worksheet with an answer key.
Curated OER
Proving Lines Parallel Homework
In this parallel lines worksheet, students solve 13 short answer and fill in the blank problems. Students determine which lines are parallel given a statement such as if these angle measures are equal then which lines are parallel?...
Curated OER
Classifying Angles: Greater Than, Less Than, or Equal to 90 Degrees?
In this angles worksheet, students analyze four angles. For each angle, students decide if it is greater, less than, or equal to a right angle. Students check the correct box.
Curated OER
Angles-Greater Than, Less Than or Equal To 90 Degrees?
In this angles worksheet, students determine whether given angles are greater than, less than or equal to 90 degrees, checking the appropriate answer. A reference web site is given for additional activities.
Curated OER
The Right Angle
In this algebra worksheet, students rewrite word problems using an algebraic equation to find the answer. There are 14 questions with an answer key.
Curated OER
Inscribed Angles
Students analyze inscribed angles and intercepted arcs and explore the relationships between the two. They investigate the properties of angles, arcs, chords, tangents, and secants to solve problems involving circles.
EngageNY
The Angle-Angle (AA) Criterion for Two Triangles to Be Similar
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...
EngageNY
The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
EngageNY
Applying Tangents
What does geometry have to do with depression? It's an angle of course! Learners apply the tangent ratio to problem solving questions by finding missing lengths. Problems include angles of elevation and angles of depression. Pupils make...
Curated OER
Toothpick Triangles
Students draw a chart (included in the lesson) to use with their investigation. They review terminology of triangles and receive toothpicks to use in the lesson. Beginning with three toothpicks, students form a triangle. They complete...
Curated OER
Linear Equations
Eighth and ninth graders solve and graph 42 different problems that include writing various equations and graphing them on a grid. First, they create a table for each equation and graph it on a grid locating the x-and y-intercepts. Then,...
Curated OER
Finding Unknown Angles
In this finding unknown angles learning exercise, 10th graders find each numbered angle's measure for 20 different angles shown in the diagrams. They calculate the size of an angle when the other two angles are known to equal 180...