EngageNY
Equations for Lines Using Normal Segments
Describing a line using an algebraic equation is an essential skill in mathematics. The previous activity in the series challenged learners to determine if segments are perpendicular with a formula. Now they use the formula to determine...
EngageNY
Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...
EngageNY
The Volume Formula of a Pyramid and Cone
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 previous...
Curated OER
Geometry - Angles Overview
Learners address 14 questions that include naming all pairs of opposite and supplementary angles for sets of intersecting lines and then, finding the measure of the unknown angle. They determine the measure of the angle that is...
EngageNY
Writing the Equation for a Circle
Circles aren't functions, so how is it possible to write the equation for a circle? Pupils first develop the equation of a circle through application of the Pythagorean Theorem. The activity then provides an exercise set for learners to...
Noyce Foundation
Surrounded and Covered
What effect does changing the perimeter have on the area of a figure? The five problems in the resource explore this question at various grade levels. Elementary problems focus on the perimeter of rectangles and irregular figures with...
Curated OER
Practice: Word Problems
Congratulations, you've just hit the word problem jackpot! Covering an incredible range of topics from integers and fractions, to percents, geometry, and much more, this collection of worksheets will keep young mathematicians busy...
Virginia Department of Education
Logic and Conditional Statements
If there is a conditional statement, then there is a hypothesis and conclusion. Pupils learn how to identify the parts of conditional statements. Class members continue to work with conditional statements and rewrite them in their many...
Curated OER
Challenge: Skills and Applications Lesson 2.3
In this geometry worksheet, 10th graders solve logic puzzles. The one page worksheet contains three questions. Answers are not included.
Virginia Department of Education
Geometry and Volume
The history of math is fascinating! Utilize a woodcut primary source image from 1492 and posters from the 1930s to help geometers apply their volume-calculation skills to real-life questions.
EngageNY
Discovering the Geometric Effect of Complex Multiplication
Does complex number multiplication have the class spinning? Here's a resource that helps pupils explore and discover the geometric effect of multiplying complex numbers. In the 14th installment in the 32-part unit groups look at the unit...
EngageNY
How Do 3D Printers Work?
If we stack up all the cross sections of a figure, does it create the figure? Pupils make the connection between the complete set of cross sections and the solid. They then view videos in order to see how 3D printers use Cavalerie's...
EngageNY
Mid-Module Assessment Task: Grade 8 Module 7
Assess pupil understanding of rational and irrational numbers with a mid-module assessment that is the 15th lesson in the 25-part series. The questions represent the objectives in the first half of the series. Topics include decimal...
EngageNY
Definition and Properties of Volume
Lead a discussion on the similarities between the properties of area and the properties of volume. Using upper and lower approximations, pupils arrive at the formula for the volume of a general cylinder.
EngageNY
What Is Area?
What if I can no longer justify area by counting squares? Lead a class discussion to find the area of a rectangular region with irrational side lengths. The class continues on with the idea of lower approximations and upper...
EngageNY
General Pyramids and Cones and Their Cross-Sections
Are pyramids and cones similar in definition to prisms and cylinders? By examining the definitions, pupils determine that pyramids and cones are subsets of general cones. Working in groups, they continue to investigate the relationships...
EngageNY
Analytic Proofs of Theorems Previously Proved by Synthetic Means
Prove theorems through an analysis. Learners find the midpoint of each side of a triangle, draw the medians, and find the centroid. They then examine the location of the centroid on each median discovering there is a 1:2 relationship....
EngageNY
Properties of Area
What properties does area possess? Solidify the area properties that pupils learned in previous years. Groups investigate the five properties using four problems, which then provide the basis for a class discussion.
Curated OER
Surface Area and Volume
For this surface area and volume worksheet, 8th graders solve 11 various geometry problems that include determining the surface area and volume for the measurements given and finding the surface area for each solid shown. Then they...
EngageNY
The Geometric Effect of Some Complex Arithmetic 2
The 10th lesson in a series of 32, continues with the geometry of arithmetic of complex numbers focusing on multiplication. Class members find the effects of multiplying a complex number by a real number, an imaginary number, and another...
EngageNY
Representing Reflections with Transformations
In the 16th lesson in the series of 32 the class uses the concept of complex multiplication to build a transformation in order to reflect across a given line in the complex plane. The lesson breaks the process of reflecting across a line...
EngageNY
Replacing Letters with Numbers
When did letters become the same as numbers? Scholars learn about substituting numbers for letters to evaluate algebraic expressions in the seventh part in a series of 36. The lesson plan focuses on expressions related to geometry, such...
Curated OER
Tale of the Tape
How can baseball and skeet-shooting be modeled mathematically? Sports lovers and young mathematicians learn how to use quadratic equations and systems of equations to model the flight paths of various objects.
Houghton Mifflin Harcourt
Developing Formulas for Circles and Regular Polygons
Formulas and procedures for finding the area and circumference are not provided on this handout, so it will be best used as a practice of already-acquired skills. It is a well-rounded assignment, however, as it includes diagrams,...