1. Big Idea Estimating to the nearest 10 or 100 helps me find what numbers are close so I can compute mentally. 8.1Essential Understanding/Question How do you find the closest 10 to a two–digit number?

2. Draw, build or write to solve. What word problem and solve it. Explain how to find the closest 10 to _______. Use pictures, numbers, or words. Pick a number. What is the closest 10 to your number. Tell how you found the closest ten. Is 34 closer to 30 or closer to 40? How do you know?

3. Big Idea Estimating to the nearest 10 or 100 helps me find what numbers are close so I can compute mentally. 8.2 Essential Understanding/Question How can you estimate a two-digit sum?

4. Show three different ways to round two numbers to 50¢. Write a word problem and solve it. Create a store where someone with 90¢ could purchase two items using different combinations. Each item must have a two digit number. How many combinations can you make? How can you estimate a two-digit sum? Define the word estimate and list three ways it can be used in the real world.

5. Big Idea Estimating to the nearest 10 or 100 helps me find what numbers are close so I can compute mentally. 8.3 Essential Understanding/Question Can you estimate a difference by subtracting tens and then looking at the ones?

6. Use three different math tools to explain or illustrate a subtracting problem using estimating. Write a word problem and solve it. Explain rounding in your own words and then explain your work to a classmate.. Can you estimate a difference by subtracting the tens and then looking at the ones? What is wrong with this problem? Sam has 7 dimes and 6 pennies. He thinks he can buy a two toys. One cost 38¢ and the other one cost 41¢. Was he able to but them? Explain why or why not.

7. Big Idea Estimating to the nearest 10 or 100 helps me find what numbers are close so I can compute mentally. 8.4 Essential Understanding/Question How can you use reasoning and estimating to determine whether there is more or less than a given amount and solve problems?

8. Write the steps of estimating. Then create a classroom poster with them. Write a word problem involving estimation, solve,and illustrate it. With a friend create a game using estimating to the nearest 10. Round the following numbers to the nearest10. 437 935 248 How can you use reasoning and estimation to determine whether there is more or less than a given amounts and solve problems?