Unit 3 Wrapping Up Addition And Subtraction Within 1000 — Unit Plan

Title	Assessment
Lesson 1 Represent Numbers in Different Ways	Let Me Count the Ways Select all the ways you could represent two hundred fifty-seven. 572 257 $200 + 50 + 7$ $20 + 500 + 7$ $200 + 40 + 17$ $100 + 140 + 7$ Show Solution B, C, and E
Lesson 2 Addition and Subtraction Situations	How Much Taller? The Statue of Liberty is 305 feet tall. The Brooklyn Bridge is 135 feet tall. How much taller is the Statue of Liberty than the Brooklyn Bridge? Explain or show your reasoning. Show Solution 170 feet. Sample response: I drew a number line and started at 135. Then I jumped 5 to 140 and 60 more to 200. I jumped 100 to get to 300. Then I jumped 5 more to get to 305. Finally, I added up all my jumps on the number line. $5+60+100+5$ is 170.
Lesson 3 Add Your Way	Add It Up Find the value of $258 + 217$ . Explain or show your reasoning. Show Solution 475. Sample response: I added the ones to get 15, the tens to get 60, and the hundreds to get 400. Then I added $15 + 60 + 400$ to get 475.
Lesson 4 Introduction to Addition Algorithms	Choose an Algorithm A diagram of the base-ten blocks that represent $138 + 425$ is shown. Use an algorithm you learned in today's lesson to find the value of the sum. Show Solution 563. Students use either algorithm from the lesson.
Lesson 5 Another Addition Algorithm	Use an Algorithm for Addition Use an algorithm of your choice to find the value of $365 + 182$ . Show Solution 547. Students use any of the three addition algorithms learned so far.
Lesson 6 Use Strategies and Algorithms to Add	Algorithm or Another Strategy? Would you use an algorithm or another strategy to find the value of $299 + 179$ ? Explain your reasoning. Show Solution Sample response: Instead of using an algorithm, I would take away 1 from 179 and add it to the 299. Then I can find $300+178$ , which is 478.
Section A Check Section A Checkpoint	Problem 1 Find the value of each sum. Use an algorithm or a strategy of your choice. $375+444$ $138+283$ Show Solution 819. Sample response: $300 + 400 = 700$ $70 + 40 = 110$ $5+4 = 9$ $700 + 110 + 9 = 819$ 421. Sample response: Problem 2 Here is how Han found the value of $684 + 237$ . What is the meaning of the two 1s above 684 in Han's calculation? Explain why Han's strategy accurately finds the value of 684 + 237. Show Solution Sample responses: The 1 above the 8 is a ten coming from $4+7$ , which is a ten and a one. The 1 above the 6 is a hundred, which comes when Han adds up the tens in the sum. He adds the ones, tens, and hundreds of the two numbers, and the two 1s help him add them all up correctly.

Lesson 7 Subtract Your Way	Subtract within 1,000 Find the value of $372 - 158$ . Explain or show your reasoning. Show Solution 214. Sample response: I made 372 with base-ten blocks. I had to trade a ten for some more ones. This gave me 12 ones and 6 tens. Then I subtracted the hundreds to get 200, the tens to get 10, and the ones to get 4. The blocks I had left showed 214.
Lesson 8 Subtraction Algorithms (Part 1)	Connect a Diagram and an Algorithm Explain how the diagram matches the algorithm. Show Solution Sample response: I can see that there are 3 hundreds, 8 tens, and 2 ones, but 1 ten has been moved over to get more ones. In the algorithm, the 80 and the 2 are crossed out to show this. The blocks that are not crossed out show the $100+10+5$ in the algorithm.
Lesson 9 Subtraction Algorithms (Part 2)	How Did Andre Subtract? Andre found the value of $739-255$ . His work is shown. Explain how he subtracted and the value he found for $739-255$ . Show Solution Sample response: First Andre wrote 739 and 255 in expanded form and stacked them. Then he subtracted 5 from 9 and got 4. Then he realized he didn’t have enough tens to subtract 50 from 30 so he decomposed a hundred from the 700 into 10 tens to get 130. 130 minus 50 is 80 and 600 minus 200 is 400. His answer is 484.
Lesson 10 Subtraction Algorithms (Part 3)	Choose the Method Use an algorithm of your choice to find the value of $419 - 267$ . Show Solution 152. Students use either of the subtraction algorithms learned so far.
Lesson 11 Analyze Subtraction Algorithms	Subtraction Reflection You’ve learned many ways to subtract large numbers, including strategies and algorithms. What is your favorite way to subtract large numbers? What’s a way that you would like to learn more about and use more? Show Solution Sample response: I like to count back by place value. I am still learning to use an algorithm in which I first write the numbers as a sum of hundreds, tens, and ones.
Lesson 12 Subtract Strategically	An Algorithm or Another Strategy? How would you find the value of $700 - 599$ ? Explain your reasoning. Show Solution Sample response: I would use a counting-up strategy because the numbers are both so close to hundreds that it would be a lot faster to count up than to use an algorithm.
Section B Check Section B Checkpoint	Problem 1 Find the value of each difference. Use an algorithm or strategy of your choice. $288 - 197$ $506-388$ Show Solution 91. Sample response: 118. Sample response: Problem 2 Here is how Elena found the value of $731 - 498$ . $\begin {align}\\ 498 + \hspace{.45cm}2 &= 500\\ 500+200&=700\\ 700+\hspace{.25cm}30&=730\\ 730+\hspace{.45cm}1&=731\end{align}$ $200+30+2+1=233$ Explain why Elena's strategy accurately finds the value of $731-498$ . Show Solution Sample response: Elena finds how much she needs to add to 498 to get 731. This is the same as the difference $731 - 498$ .

Lesson 13 Multiples of 100	Locate, Label, and Name Locate and label 185 on the number line on which it belongs. Name the closest multiple of 100 to 185. Show Solution 200
Lesson 14 Nearest Multiples of 10 and of 100	Closest Multiples of 10 and of 100 What is the nearest multiple of 100 to 162? Is it 100 or 200? Explain or show your reasoning. What is the nearest multiple of 10 to 162? Is it 160 or 170? Explain or show your reasoning. Show Solution 200. Sample response: 150 is right in between and 162 is greater, so it’s closer to 200 than to 100. 160. Sample response: From 162, it’s 8 counts on to get to 170, but only 2 counts back to 160, so 160 is closer than 170.
Lesson 15 Round to the Nearest Ten and the Nearest Hundred	Round It Twice Round 237 to the nearest ten. Show or explain your reasoning. Round 237 to the nearest hundred. Show or explain your reasoning. Show Solution 240. Sample response: 237 is between 230 and 240. It is closer to 240, since it’s only 3 away. 200. Sample response: 237 is between 200 and 300. It is closer to 200, since it’s under 250.
Lesson 16 Round and Round Again	What Is Clare’s Mystery Number? Clare says she’s thinking of a mystery number and gives these three clues: The number is even. The number rounded to the nearest ten is 270. The number is between 260 and 280. What are 2 numbers that could be Clare's mystery number? Show Solution Any 2 of 266, 268, 270, 272, or 274.
Section C Check Section C Checkpoint	Problem 1 What is 572 rounded to the nearest ten? What is 572 rounded to the nearest hundred? Is there a number that rounds to the nearest hundred as 300 and to the nearest ten as 240? Explain or show your reasoning. Show Solution 570 600 No. Sample response: A number that rounds to the nearest hundred as 300 is at least 250. This means that 250 is the least the number can be rounded to the nearest ten. Problem 2 What is the least number that rounds to the nearest ten as 280? Explain or show your reasoning. What is the greatest number that rounds to the nearest ten as 280? Explain or show your reasoning. Show Solution 275. Sample response: Because 274 is closer to 270 than 280 but 275 is halfway between 270 and 280 and we round it to 280. 284. Sample response: Because if I add 1 more, then I get 285, which rounds to 290.

Lesson 17 Does It Make Sense?	Beads in the Bin There are 124 beads in the bin before 96 more beads are added. Then 53 beads are used to make a bracelet. Tyler says there are 273 beads in the bin now. Explain why Tyler’s statement doesn’t make sense. Show Solution Sample response: Tyler’s statement doesn’t make sense because if about 100 beads are added to 124 beads, that’s about 225 beads. Then about 50 beads are used to make a bracelet, which would take the number back down close to 175 beads. Using 50 beads to make a bracelet would make fewer beads in the bin, not more beads.
Lesson 18 Diagrams and Equations for Word Problems	Equation Match Andre had 451 beads. 125 beads were blue. 223 beads were pink. The rest of the beads were yellow. How many beads were yellow? Which equation matches this situation? Explain your reasoning. $451 + 125 + 223 = {?}$ ${?} + 125 + 223 = 451$ $451 = 125 + 223 - ?$ Show Solution B. Sample response: The 125 and the 223 were just part of the total of 451. The missing number also should be added as part of the total of 451.
Lesson 19 Situations and Equations	How Many Beads? Andre has 196 beads. He uses 48 beads to make a craft. Then he gives 30 beads to a friend. How many beads does Andre have left? Write an equation with a letter for the unknown quantity to represent this situation. Solve the problem. Explain or show your reasoning. Show Solution $196-48-30 = {b}$ 118 beads. Sample response:
Lesson 20 More Practice to Represent and Solve	Reflection Describe something you really understand well after today’s lesson, or describe something that was confusing or challenging. Show Solution Answers vary.
Lesson 21 Classroom Supplies	No cool-down
Section D Check Section D Checkpoint	Problem 1 Elena has 372 pennies in her piggy bank. Jada has 119 pennies in her piggy bank. Elena says that if they put their pennies together they have about 500. Do you agree with Elena's estimate? Explain or show your reasoning. Show Solution Sample responses: Yes. Elena has almost 400 pennies and Jada has a little more than 100 so together that's about 500 pennies. No. Elena is almost 30 pennies short of 400 and Jada has only about 20 pennies more than 100. Together, they have fewer than 500 pennies. Problem 2 Andre has 138 trading cards. He gets 3 more sets of 8 cards. Explain why the diagram represents the situation. A Write an equation that matches the diagram. How many cards does Andre have now? Show Solution Sample response: The diagram shows Andre's 138 cards and then 3 groups of 8 cards more. $138 + (3 \times 8)= {?}$ 162 cards. Sample response: $3 \times 8 = 24$ and $104 + 24 = 128$ . Problem 3 There are 4 tables in the cafeteria, with 9 students eating lunch at each table. There are also 177 students waiting in line for lunch at the cafeteria. How many students are there in the cafeteria altogether? Write an equation for the situation. Use a "?" for the unknown. Find how many students there are in the cafeteria altogether. Show Solution $177 + (4 \times 9) = {?}$ 213 students. Sample response: $4 \times 9 = 36$ , $177 + 30 = 207$ , $207 + 6 = 213$ .