Unit 5- Large Numbers and Landmarks

During this unit, students study place value in large numbers, and complete a final study of addition and subtraction strategies. Students are expected to leave Grade 4 using a variety of strategies, including the U.S. standard algorithms, to fluently solve multidigit addition and subtraction problems.

In our math class, students spend time discussing problems in depth and are asked to share their reasoning and solutions. It is important that children solve math problems accurately and efficiently in ways that make sense to them.

Math Words and Ideas

1- Addition Strategies

2- Place Value: Large Numbers

3- Comparing Addition Notation

4- U.S. Standard Algorithm for Addition

5- Subtraction Problem Types

6- U.S. Standard Algorithm for Subtraction

7- Subtraction Strategies

8- Rounding Large Numbers

Investigations Games Unit 5

Non Investigations Games

Activities to Try at Home

Making Sense of Large Numbers With your child, look for large numbers in the newspaper, on packages, on signs, and around your home and neighborhood. Talk together and ask questions about the numbers. You might ask, “How much would the car cost if the salesperson offered a $2,500 discount?” You might ask, “If 45,000 people went to the basketball game at Central Stadium last night, how many seats were empty?”

Adding and Subtracting Distances Find opportunities to give your child first-hand experiences with distances, such as the number of miles driven across town or on a long trip. If you drive, show your child the odometer on your car, and ask your child to help you figure out how far it is to the grocery store or the playing field. You might ask, “If we start at 24,538 miles, and when we get to the store the odometer reads 24,542, how far have we gone?”

How Did You Solve That? Ask your child to tell you about how he or she is adding and subtracting. Show that you are interested in these approaches. Because these strategies may be unfamiliar to you, listen carefully to your child’s explanation; you might even do a problem or two, using the new procedure. Let your child be the teacher!