Adding Like Fractions
Fourth Grade Lesson Plan
Objectives
Students will understand how to add fractions. Students will be able to demonstrate using unifix cubes how to make number sentences adding like fractions. Students will also play a game where to help them learn how to write correct number sentences.
Content
During this lesson, students will use unifix cubes to demonstrate how to add fractions. They will look at them as wholes and then break them apart to think about how to add up different parts of the whole. For the second part of the lesson, students will play a game with a partner where they are racing to complete a whole.
Materials
Unifix Cubes
Wooden Cubes with sides labeled 1/2, 1/3, 1/4, 1/6, 1/8, and 1/12
Game board (one for each student and one transparency)
Record Sheet (one for each student)
Crayons
Fraction Wheel Sheet (one for each student)
Introduction (15 minutes)
Ask students what they know about adding fractions. Can you add fractions with the same denominator? Show them 4 unifix cubes put together and ask how many parts there are in the whole. Ask them what would happen if you took one of the unifix cubes and added it to another. How many fourths would you have now? Give the students several unifix cubes to work with while you give them the following examples:
- Connect 5 unifix cubes together. What would happen if you added 2/5 and 1/5? What about 2/5 and 2/5?
- Connect 6 unifix cubes together. What happens if you add 1/6 and 1/6? What about 2/6 and 1/6?
- Connect 12 unifix cubes together. What do you get if you add 1/12 and 1/12? How about 3/12 and 4/12
Through all these examples, write their number sentences on the board, to model what you want them to do in the next activity. Explain that the top number is the numerator and the bottom number is the denominator and that when you add fractions, you only add the numerators.
Activity (35 minutes)
- Put the game board transparency on the overhead. Have students tell you what each square represents (1/2, 1/3, 1/4, 1/6, 1/8, and 1/12). Show several examples of how to add up different kinds of fractions. Write the number sentences on the transparency as you say them to further model how you want the students to play the game.
- Tell students that they will be playing a game where they will be trying to add up fractions as fast as they can. Put the students into pairs and give each student a game board and a record sheet. Give each pair of students a wooden cube.
3.Tell students that they should pick someone to go first and that they are going to roll the wooden cube and color in one square on their game board that corresponds with the fraction they rolled. Then it will be the other player’s turn. The other player will do the same thing. The students will continue rolling and coloring until they roll something they have already rolled. For example, if they rolled a 1/3 on their first roll and a 1/3 on the third roll, they will stop and record on their record sheet the number sentence that goes with those rolls (1/3 + 1/3 = 2/3). Then play will continue until the students have filled up their game boards. The player that fills their board first wins.
Closure (10 minutes)
Ask students what they know about adding fractions. What kinds of kinds of fractions do they know how to add together? Do they add the numerators or the denominators? After finishing their game, students will begin to work on the wheel worksheet. Explain what you want them to do: add the number in the middle to the number in the outside. Additionally, have students pick one of the sentences from each wheel to write out on the back. If students do not finish, have them complete the sheet for homework.
Assessment
Listen to the students as they discuss adding fractions and the number sentences that they are making. Also, look at the number sentences that they record on their record sheets to see if they understand how to transfer the sentences from the game they are playing. Finally, the fraction wheel sheet will also provide insight into the students’ understanding.