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Geometric Measurement

Area, perimeter, and volume calculations for two- and three-dimensional figures. Develops spatial reasoning through the application of measurement formulas and unit conversions.

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Videos

How to Calculate the Perimeter of a Square

How to Calculate the Perimeter of a Square

This educational video provides a clear, step-by-step tutorial on how to calculate the perimeter of a square. It begins by defining perimeter as the total distance around a figure and reviewing the key property of a square: that all four sides are of equal length. This foundational knowledge is used to derive the formula for the perimeter of a square (4 × length) as a more efficient alternative to repeated addition.

MatholiaChannelMatholiaChannel

1min 55s

Calculating Area by Decomposing Irregular Shapes

Calculating Area by Decomposing Irregular Shapes

This educational video provides a step-by-step tutorial on how to calculate the area (square footage) of an irregular, composite polygon. The instructor uses a clear, high-contrast digital whiteboard to demonstrate the concept of decomposing a complex shape into simpler, manageable rectangles. The lesson begins with a review of the basic area formula for a rectangle before diving into a complex problem involving missing side lengths and multiple subsections. The core theme is the strategy of decomposition—breaking a difficult problem into smaller, solvable parts. The video covers identifying distinct rectangular sections within an irregular shape, deducing missing side lengths using addition and subtraction of parallel sides, and calculating individual areas. It concludes by summing these partial areas to find the total square footage, reinforcing the additive property of area. This resource is highly valuable for upper elementary and middle school mathematics classrooms. It addresses the common student struggle of finding derived dimensions (missing side lengths) on composite figures. Teachers can use this video to model problem-solving strategies for geometry standards related to area, or as a flipped classroom resource for students to review the mechanics of decomposition and area calculation at their own pace.

The Organic Chemistry TutorThe Organic Chemistry Tutor

6mins 9s

Calculating the Lateral and Total Surface Area of a Cone

Calculating the Lateral and Total Surface Area of a Cone

This math tutorial provides a step-by-step demonstration of how to calculate both the lateral area and total surface area of a cone. Using a specific example with a radius of 5 inches and a height of 12 inches, the narrator guides viewers through the necessary formulas and calculations. The video visualizes the geometry by drawing a cone and labeling the key dimensions, making abstract formulas concrete. A key component of this lesson is the integration of the Pythagorean theorem. Since the problem provides the vertical height rather than the slant height, the narrator shows how to identify the right triangle within the cone to solve for the missing slant height dimension. This connects 2D triangle geometry concepts with 3D solid geometry. The video then proceeds to substitute these values into the standard formulas for lateral area ($\pi rl$) and total surface area (Base Area + Lateral Area). For educators, this video serves as an excellent model for solving multi-step geometry problems. It reinforces the importance of distinguishing between height and slant height—a common student error. The clear, handwritten derivations allow students to follow the logic line-by-line, making it suitable for introducing the concept, reviewing for exams, or providing support for homework assignments involving 3D geometric measurements.

The Organic Chemistry TutorThe Organic Chemistry Tutor

3mins 2s

Understanding Angles, Degrees, and How to Measure Them

Understanding Angles, Degrees, and How to Measure Them

This engaging educational video introduces students to the fundamental concepts of measuring angles using degrees. It clarifies the distinction between measuring length with rulers and measuring rotation with degrees, using clear visual animations to demonstrate how an angle is formed by rotating a ray around an axis. The video takes viewers on a journey from 0 to 360 degrees, stopping to identify and define critical angle types including acute, right, obtuse, and straight angles. The content covers essential geometric vocabulary and measurement techniques. It explains the degree symbol, demonstrates how a protractor is used to measure unknown angles, and visually defines the four quadrants of rotation. Special emphasis is placed on memorizing key benchmarks like 90 degrees (right angle) and 180 degrees (straight angle). The video concludes with practical application problems, showing students how to calculate unknown angle measurements using the properties of complementary and supplementary angles. For educators, this video serves as an excellent primary resource for introducing geometry units or reinforcing measurement skills. The clear, step-by-step animations make abstract concepts concrete, while the inclusion of humor (comparing temperature degrees to geometric degrees) helps maintain student engagement. The final segment connecting angle properties to basic algebraic thinking provides a natural bridge for middle school math curriculums.

mathanticsmathantics

9mins 17s

How to Find Area by Counting Square Tiles

How to Find Area by Counting Square Tiles

This educational video provides a clear, step-by-step introduction to the concept of area using counting methods. It demonstrates how to determine the area of various 2D shapes by counting the number of unit square tiles they contain. The video progresses from simple rectangles to irregular polygons, building foundational understanding of measurement. The content covers two primary skills: finding area by counting whole square units and calculating area for shapes that include half-square (triangular) units. Through four distinct examples (Figures A, B, C, and D), the video visually scaffolds the learning process, starting with basic counting and advancing to the concept that two half-units equal one whole unit. This resource is highly valuable for early elementary mathematics classrooms introducing geometry and measurement. It visualizes the abstract concept of "area" as the amount of space a shape covers, providing a concrete strategy for students before they move on to using multiplication formulas. The inclusion of composite shapes helps prevent the misconception that area is only length times width.

MatholiaChannelMatholiaChannel

2mins

Finding the Side Length of a Square From Its Area

Finding the Side Length of a Square From Its Area

This video provides a clear, step-by-step tutorial on how to determine the side length of a square when the area is known. Through three distinct examples using different colors and units (cm² and m²), it guides viewers through the logic of inverse operations without explicitly introducing complex algebraic notation. The narrator explains that since a square's area is length multiplied by length, finding the side means identifying a number that multiplies by itself to equal the given area. The video explores key mathematical themes including geometry, measurement, and the relationship between multiplication and area. It reinforces the concept of "perfect squares" (9, 25, 64) and visually demonstrates how to use multiplication facts to solve for unknown dimensions. The repetitive structure serves to build confidence and fluency with the procedure, allowing students to practice the thinking process three separate times. For educators, this resource is an excellent tool for introducing the concept of square roots in a concrete, geometric context. It bridges the gap between basic multiplication and algebraic thinking. Teachers can use it to help students visualize why the inverse of squaring a number helps find geometric dimensions, making it suitable for lessons on area, perimeter, and pre-algebraic reasoning.

MatholiaChannelMatholiaChannel

3mins 5s

Materials

Composite Polynomials Worksheet

Composite Polynomials Worksheet

A two-page printable high school Algebra I worksheet containing 6 multiple-choice problems on finding the perimeter and area of composite rectangular figures using polynomial addition, subtraction, and multiplication, featuring crisp, bold SVG geometric diagrams with high-contrast dimension labels and student workspaces.

JW

Jessica Waters

Polygon Area Guided Notes

Polygon Area Guided Notes

A 3-page scaffolded, large-font, black-and-white guided lesson sheet for 6th graders with foundational math proficiency. Features visible unit measurement grids behind all geometric shapes for counting base and height, zero overlap between text labels and shapes, and clear step-by-step models for parallelograms, triangles, and composite polygons.

MJ

Meg Jones

Prism Volume Worksheet

Prism Volume Worksheet

A two-page student practice worksheet featuring three rectangular prism volume problems on page one and five three-factor multiplication equations on page two with large white calculation boxes for handwriting work.

SM

Susannah Malloy

Deep Ocean Expedition Work Packet

Deep Ocean Expedition Work Packet

A rigorous 4-page 5th-grade Deep Ocean Expedition work packet with instructional scaffolds. Includes an informational text on Hadal Zone adaptations with vocabulary callouts and text-dependent questions, an engineering proposal writing task with graphic organizers and transition supports, 3-digit by 3-digit multiplication grid algorithms, and area and volume missing dimension challenges.

CZ

Claire Zietsman

Grade 4 Math Priority Pacing Guide

Grade 4 Math Priority Pacing Guide

A comprehensive 5-page standards-aligned Grade 4 Mathematics curriculum pacing guide for i-Ready Classroom Mathematics, specifically incorporating the 14 designated District Priority Standards across 4.OA, 4.NBT, and 4.NF. Calibrated to the Massachusetts Curriculum Frameworks to guarantee 100% completion of all district priority standards before May 1, featuring explicit district priority badging, unit-by-unit pacing dates, strategic triage rationales for non-priority topics, and a Tier 2 prerequisite intervention bridge.

AS

Ashley Santiago

Problem Scale Visual Poster

Problem Scale Visual Poster

A clear 1-7 problem scale visual anchor chart for fourth graders, differentiating small versus big problems with an arrow scale showing when to ignore, solve with kindness, or tell a teacher.

MB

Michelle Bentley

Sequences

Packet Master TOC document

Unit 6 Equal Groups and Multiplication

A comprehensive Grade 2 math packet focused on skip counting, repeated addition, arrays, and equal groups.

N

nmack

39
Equation Balancing Student Packet

Distance Detectives

A highly visual geometry unit focused on applying algebraic formulas to coordinate planes. Students use coordinate grids, step-by-step graphic organizers, and tactile representations to solve real-world distance and segment length problems.

D

deeohnny.jackson

64
Math Blueprint Week 1 Booklet (Definitive)

Math Blueprint Spiral

A 7-week comprehensive math review sequence designed to prepare 6th-grade students for North Carolina state testing, covering Number Systems, Ratios, Expressions, Geometry, and Statistics.

MK

Michell Kisler

27
Camp Multi-Math Worksheet

Math Review Adventures

A collection of themed end-of-year math review adventures for different grade levels, focusing on spiraling key standards and problem-solving.

DB

Deborah Burton

21
3 Reads Strategy Poster

Math Blueprints Grade 5

A comprehensive set of math supports for 5th-grade students in a co-taught environment. Each unit includes visual vocabulary, worked examples, cloze-style guided notes, and exit tickets featuring a 'Mistake of the Day' analysis.

HJ

Hope Joel

23
Plunder Plan Teacher Guide

Pirate Math Plunder

A pirate-themed 3rd grade math review escape room where students solve puzzles involving geometry, multiplication, division, fractions, and word problems to find the hidden treasure.

DG

Danielle Garland

12