## Description

# What our Fractions: Add and Subtract Unlike Denominators lesson plan includes

Lesson Objectives and Overview: Fractions: Add and Subtract Unlike Denominators teaches students how to add or subtract fractions with unlike denominators. They will know how to add or subtract fractions with like denominators. Students practice solving problems as a part of this lesson. This lesson is for students in 5th grade.

### Classroom Procedure

Every lesson plan provides you with a classroom procedure page that outlines a step-by-step guide to follow. You do not have to follow the guide exactly. The guide helps you organize the lesson and details when to hand out worksheets. It also lists information in the blue box that you might find useful. You will find the lesson objectives, state standards, and number of class sessions the lesson should take to complete in this area. In addition, it describes the supplies you will need as well as what and how you need to prepare beforehand. The only supplies you will need for this lesson are scissors. To prepare for this lesson ahead of time, you can gather the supplies and copy the handouts.

#### Options for Lesson

Included with this lesson is an “Options for Lesson” section that lists a number of suggestions for activities to add to the lesson or substitutions for the ones already in the lesson. All of the optional adjustments for this lesson are for the activity. You can have students create their own War problems on index cards, creating various levels of difficulty. Students can play in groups of three or four. If you have students who are struggling, you can make sure they only use denominators under 6. Finally, if you have students who need more of a challenge, you can either use larger numbers or incorporate three numbers into the expression to make it more difficult.

### Teacher Notes

The teacher notes page includes a paragraph with additional guidelines and things to think about as you begin to plan your lesson. This page also includes lines that you can use to add your own notes as you’re preparing for this lesson.

## FRACTIONS: ADD AND SUBTRACT UNLIKE DENOMINATORS LESSON PLAN CONTENT PAGES

### Fractions – Add and Subtract Unlike Denominators

The Fractions: Add and Subtract Unlike Denominators lesson plan includes three content pages. The lesson begins by stating that you have to have a common denominator (the same denominator) to add or subtract fractions. The bottom number in a fraction is called the denominator. The lesson shows examples of common and unlike (different) denominators. In order to find a common denominator, you need to find the least common multiple.

For the example problem 2/3 + 1/9, we must first find the least common multiple of 3 and 9. Multiples of 3 are 3, 6, 9, and multiples of 9 start with 9. Therefore, the least common multiple is 9. Next, you must multiply both the numerator and the denominator by 3 in the first fraction to create the common denominator, because 3 x 3 = 9 (the new denominator). The original fraction is 2/3, so the new one is 6/9 (2 x 3 = 6 and 3 x 3 = 9). You can then add the fractions together easily. 6/9 + 1/9 = 7/9.

The lesson next shows another addition example and a subtraction example that uses the same process. It then shows an example that includes a mixed number. For mixed numbers, you must first change the mixed number into an improper fraction. You then solve using the same method! Your final answer can be written either as an improper fraction or you can change it back to a mixed number.

## FRACTIONS: ADD AND SUBTRACT UNLIKE DENOMINATORS LESSON PLAN WORKSHEETS

The Fractions: Add and Subtract Unlike Denominators lesson plan includes three worksheets: an activity worksheet, a practice worksheet, and a homework assignment. You can refer to the guide on the classroom procedure page to determine when to hand out each worksheet.

### WAR ACTIVITY WORKSHEET

For the activity worksheet, students will play a fun game of War using the provided cards (which they will need to cut out of the worksheet). To play, each student will flip over a card and solve the problem. The highest card wins!

### SOLVE THE PROBLEMS PRACTICE WORKSHEET

The practice worksheet asks students to solve 12 addition or subtraction problems. They must show their work and circle their answer.

### FRACTIONS: ADD AND SUBTRACT UNLIKE DENOMINATORS HOMEWORK ASSIGNMENT

For the homework assignment, which is structured in the same way as the practice worksheet, students will solve 12 addition or subtraction problems. They must show their work and circle their answer.

### Worksheet Answer Keys

This lesson plan includes answer keys for the practice worksheet and the homework assignment. If you choose to administer the lesson pages to your students via PDF, you will need to save a new file that omits these pages. Otherwise, you can simply print out the applicable pages and keep these as reference for yourself when grading assignments.