Third Grade - MATH
5: Math
Unit 1: Multiplication and Division I
Lesson 3
Arrays and Equal Groups
Students draw and build arrays (for example a 5 by 6 array) using counters or snacks and write corresponding repeated-addition and multiplication sentences. They match arrays to multiplication sentences, find products, and use skip-counting on arrays (e.g., circling columns and counting by 5 to get 6×5=30). Students model equal groups with counters on plates and translate those groupings into multiplication expressions and products.
Lesson 4
Repeated Addition and Number Lines
Students are asked to draw and interpret arrays (for example, "4 by 3 or 3 by 4 array") and to model multiplication facts using arrays and equal groups. Students create repeated-addition sentences (e.g., 3+3+3+3 for 4×3) and represent multiplication on number lines to find products. In Activity 4 students use dominoes to generate multiplication sentences and then model each sentence by drawing an array and writing the corresponding repeated addition and number-line representations.
Lesson 5
Multiplication and the Abacus
Students are asked to use the abacus to show arrays such as a 4 by 5 array and to count the beads to find the product (e.g., 4×5 → 20). Students write multiplication sentences for given abacuses and color beads to represent multiplication sentences on the "Arrays on the Abacus" activity. Multiple activities require students to show groups (e.g., 3 groups of 5, 10 groups of 4), identify the corresponding multiplication sentence, and find the product.
Lesson 6
The Commutative Property of Multiplication
Students create and compare arrays (for example, building a 2×5 and a 5×2 array with 20 counters) and match dot grids to multiplication sentences. They draw arrays on the whiteboard, use counters and an abacus to form equal groups, and complete activity pages that pair multiplication facts with corresponding rectangular dot grids. In the wrap-up, students use 20 counters to make arrays and list multiplication sentences that produce the product 20.
Unit 4: Multiplication and Division II
Lesson 2
Multiples of 6 and 7
Students color multiples on a 10×10 multiplication grid and complete multiplication tables for 6 and 7, producing arrays of products. Students are asked to "read 6 times 7 as 6 groups of 7" and use an abacus to show 6×7 as 6 rows with 7 beads each. Students fill input/output tables where they multiply inputs by 7 and record outputs, reinforcing the idea of rectangular arrangements of rows and columns representing products.
Lesson 6
Distributive Property of Multiplication
Students use counters to create rectangular arrays (for example a 6×4 array) and name the array with a multiplication sentence. Students break the array into two smaller arrays using a straw, write each smaller array as a multiplication sentence (for example (2×4)+(4×4)), and show that the sum equals the original array's product. The Student Activity Pages include a tiled 5×6 grid with 5×6=30 and the breakdown 5×2 + 5×4 = 30, and multiple examples (e.g., 6×9 = (6×4)+(6×5)) where students find products of tiled arrays and add them.
Lesson 10
Problem Solving Using Multiple Operations
Students are asked to treat pictured arrangements as arrays in Activity 1 (Snail Parade), including an explicit example of recognizing a 5 by 5 array as 25 and subtracting 3 to get 22. Activity 2 (Chinese Checkerboard) asks students to form equal groups, circle groups of 10, and use multiplication (10×12+1) to count many dots. Multiple problems and pages prompt students to use multiplication to represent repeated equal groups and to write number sentences that combine multiplication and addition.
Unit 5: Area and Perimeter
Lesson 2
What Is Perimeter?
Students use colored tiles to construct rectangles (a 4-inch by 4-inch square said to "require 16 tiles") and make 6-inch by 4-inch and 3-inch by 8-inch rectangles in Activity 2. Students measure tile side length (1 inch) and physically assemble whole-number side-length rectangles. The lesson prompts students to manipulate tiles and notes the number of tiles needed for at least one rectangular configuration.
Lesson 6
What Is Area?
Students fill a 6 by 4 rectangle with one-inch tiles and count 24 tiles, and they fill the other boxes to get areas of 12 and 8 square inches. Students are asked to build shapes with a given number of tiles (e.g., make a 3 by 5 rectangle or an irregular shape with 15 tiles) and observe that each shape contains that many square units. In Activity 3, students roll two dice to color rectangles '2 across' and '3 down' (6 squares) or '4 across' and '6 down' (24 squares) and write the area inside each rectangle.
Lesson 7
Calculating Area
Students build rectangles on the interactive Area Builder grid and are asked to find areas first by counting unit squares and then by multiplying the side lengths (examples: 3×4→12, 5×6→30). The "Make These Areas!" activities require students to construct shapes with unit squares or pipe cleaners, draw them, label side lengths, and write number sentences (e.g., 2×5=10). Outdoor/indoor activities have students create whole-number-sided rectangles with chalk or tape, measure sides in whole units, and compute and label areas as square units.
Lesson 8
More Work With Area
Students draw and shade rectangles and squares on centimeter grid paper (Activity 1, Design Your Garden, laminated grid wrap-up), which has them tile figures with unit squares. The Skills section explicitly says students will "Multiply side lengths to find areas of rectangles with whole-number side lengths," and tasks such as drawing a rectangle with sides 8 cm and 5 cm and writing 40 sq. cm require multiplication of whole-number side lengths. The web activity instructs students to cover shapes by clicking and dragging colored squares to form rows and columns and then practice the numerical area equation, linking the tiling (counting unit squares) to a multiplication expression.
Lesson 9
Creating With Perimeter and Area
Students are instructed to fill whole squares on centimeter grid paper for both the "Measuring My Name" and "My Own Creature" activities, then "figure out the perimeter and the area" for their designs, which requires tiling and counting unit squares. The "Getting To Know My Creature" sheet asks students to find the area for six body parts and a total area, reinforcing area-by-tiling practice. The lesson's Skills list explicitly states that students will "Multiply side lengths to find areas of rectangles with whole-number side lengths in the context of solving real world and mathematical problems."
Lesson 10
Problem Solving With Perimeter and Area
Students draw and lightly trace four-sided shapes and rectangles on centimeter grid paper, effectively tiling the rectangles with unit squares. In Activity 1 they list and create specific rectangles (for example 15×3) and then find each area, using a decomposition example ((8×3)+(7×3)=24+21=45) that connects counting tiles to multiplication. Activity 2 and the Food Court activity have students count squares inside shapes on the grid to determine area and also multiply side lengths to find areas, and the Skills section explicitly states multiplying side lengths to find areas of whole-number rectangles.
Lesson 11
Unit Test
Students are given laminated grid paper and asked to draw specific rectangles and squares (e.g., square with area 64, rectangle with area 72), which requires placing shapes on unit grids (tiling). The Unit Review asks students to explain how they found area (example: a 7 in. square with area 49) and states that finding area requires multiplying two sides, and the Student Activity Pages include grid tasks that ask students to "Draw the area" for given area values (e.g., 25 as 5 by 5). The skills list explicitly requires students to "Multiply side lengths to find areas of rectangles with whole-number side lengths" and to "Relate area to the operations of multiplication and addition."
Final Project
Shapesville
Students are given building cards that state areas and one side length (e.g., Building #1: area 54 sq. in and height 4 in) and are asked to determine missing side lengths and window dimensions. The Skills section explicitly lists "Multiply side lengths to find areas of rectangles with whole-number side lengths" and Step 5 lists calculated dimensions (e.g., width of 6 in for Building #1), showing students compute dimensions from area and arrange windows in rows and columns (e.g., 3 rows of 2 windows). Day 2 asks students to explain how they found perimeters and areas, and a linked Area Blocks game provides an activity that supports tiling practice.
Unit 6: Fractions
Lesson 2
Naming Fractions
The basic skills review presents a geometry word problem in which students must decide whether a square garden with sides of 6 feet can be covered by a 25 sq. ft. bag of fertilizer, which requires finding the garden's area. The answer key indicates students use multiplication in other contexts (e.g., 10×6=60 for donuts), showing students practice multiplying whole numbers to find totals. The lesson includes several computation tasks that require calculating areas or totals and comparing to given areas.
Lesson 7
Equivalent Fractions
In Day 2 Activity 3, students are asked to draw three rectangles that are each 4 by 2 on laminated grid paper and to divide and shade them into 2, 4, and 8 parts so the colored regions look the same. The activity uses laminated grid paper, which provides a tiled grid that could be used to represent unit squares within the 4 by 2 rectangles. The Basic Skills Review includes a question about whether a 9-by-9 square meets an 80 sq. ft. requirement, which requires comparing an area computed from whole-number side lengths.
Unit 7: Geometry
Lesson 4
Getting To Know Specific Quadrilaterals
Students are asked to create squares and rectangles on a geoboard and on laminated grid paper, giving them tools that could be used to count unit squares. The Basic Skills Review includes a problem about a room of 42 sq. ft. and asks whether a square rug with side length 7 ft will fit, showing the multiplication 7×7=49. Interactive grid-based tools and grid paper are referenced multiple times for constructing and exploring quadrilaterals.
Lesson 6
Dividing Shapes
Students are asked to draw a 3 by 4 rectangle on grid paper where each small square equals one square centimeter and are asked, "What is the area of this rectangle?" The lesson explicitly tells students they can find area two ways: by multiplying the side lengths or by counting the unit squares that tile the rectangle, and it concludes that the area is 12 square centimeters. Students are also given colored tiles and encouraged to use them to find and partition areas, reinforcing tiling and counting.
Unit 9: Skills Review
Lesson 3
Reviewing Perimeter and Area
Students are given laminated grid paper and asked to draw a rectangle with sides 10 cm and 7 cm, then find its area (70 cm²). The teacher prompts or reminds students to figure area by multiplying the length and width. Students are also asked to use the grid paper to draw as many rectangles and squares as they can with specified areas (12, 15, 16), with suggested factor pairs for each area. The lesson includes an interactive 'Area Blocks' activity and a video to reinforce constructing area with unit squares.
Lesson 4
Reviewing Geometry
Activity 2 asks students to draw a rectangle that has an area of 15 square centimeters on grid paper, reminding them that each square is one square centimeter and specifying the rectangle should have sides 3 and 5 centimeters long. Students are asked to create the rectangle by filling 15 unit squares and then divide that tiled rectangle into thirds so each third has five squares. The task of drawing on the grid and counting squares directly engages students in finding area by tiling unit squares.
