Chapter 11: This week, our class will begin a new unit called “Measure and Estimate Lengths.” In this chapter, your child will learn to measure objects and estimate measurements. He or she will learn to measure in metric units (centimeters and meters) as well as in customary units (inches, feet, yards). He or she will learn which tool is appropriate to measure objects. For example, a yardstick is used to measure a table rather than an inch ruler.

The vocabulary words for this chapter are:

• Centimeter
• Meter
• Estimate
• Foot
• Inch
• yard

 

NOTE: Due to Presidents’ Day on Monday and our 2nd-grade field trip to CSU Spur on Wednesday, we will have a shorter week of lessons.

Our learning targets for this week are:

• We will begin with a unit pre-test on Tuesday.
• Measure the length of an object in centimeters. Students will use a centimeter ruler to measure the length of an object. They will tell how long the object is and explain how to use the ruler correctly to measure in centimeters.
• Measure the length of an object in centimeters or meters. Students will decide whether an object should be measured in centimeters or meters. They will measure the object using the appropriate tool and tell how long it is.

 

Ways to Support Math at Home: Here are a few ways to engage with your student.

• Ask your student to select various items around the home to measure. Have your child measure each object in centimeters and then in inches. Talk about why the measurements are different. Ask, “Why does it take more centimeters than inches to measure the same object?”
• Ask your student to measure a larger object or area, such as the length of your car or the length of his or her bed. Ask your child to decide which tool is most appropriate to measure that object. Then ask, “Why is it not a good idea to measure that object with an inch ruler or in centimeters?”
• Have your child practice estimating the lengths of various objects. Ask, “About how long do you think the table is?” Talk about his or her estimates and then measure the object. Then discuss whether the estimates were close or not.
• Model other scenarios, making sure to use terms such as “estimate,” “appropriate tool,” and “measure.”
  

This week, we will wrap up Chapter 9, “Add Numbers within 1,000.” On Thursday and Friday, students will review the material they have learned and then take the Chapter 9 post-test and the Chapter 10 Pre-Test. Chapter 10 focuses on subtracting 3-digit numbers.

Our learning targets for this week are:

1. Add up to 4 two-digit numbers. Students will find compatible numbers in the ones place and add those first. Then your child will add the other numbers in the ones place. Finally, they will add the ones, tens, and hundreds to find the sum, and regroup, as necessary. Check out this video that explains how to add up to four 2-digit numbers.

 

2. Choose and explain a strategy to use while adding. Students will choose a strategy to add two numbers, solve for the sum, and explain the strategy they used to find the answer.

This week, we will continue Chapter 9, “Add Numbers within 1,000.” In this chapter, your child is learning to add three-digit numbers with sums up to 1,000. The vocabulary phrase for this chapter is compatible numbers.

Our learning targets for this week are:

• Use partial sums to add 3-digit numbers. This video explains how we use partial sums to add 3-digit numbers.
• Use Models to regroup and add 3-digit numbers. Students will use base ten blocks or make sketches to help them solve.
• Add 3-digit numbers. In this lesson, students will explain when regrouping is needed. Then they will show 10 ones regrouped as 1 ten or 10 tens regrouped as 100. This video explains the strategy.

 

Ways to Support Math at Home

• When shopping, ask your student to add the price of 2 or 3 items to determine the total cost. Use whole-dollar amounts only. Ask your student whether a given amount is enough money to buy the items.
• Have your student be the scorekeeper when playing a game as a family. Ask what strategy he or she uses to total each player’s score. Have your student explain the strategy.
• Have your student add to find the total number of pages that he or she reads in a week. Have your student add to find the new total of pages each time he or she reads. Challenge your student to set a goal and read X number of pages that you determine for the week.
• Model other scenarios, making sure to use terms such as “total,” “sum,” ”addend,” “strategy,” and “compatible numbers.”
  

This week, we will begin Chapter 9, “Add Numbers within 1,000.” In this chapter, your child will learn to add three-digit numbers with sums up to 1,000. Students will use various strategies such as place value, open number lines, and compensation to add one-, two-, and three-digit numbers. Your child will also identify when regrouping is needed to add numbers.

The vocabulary phrase for this chapter is compatible numbers.

Our learning targets for this week are:

• Use mental math to add 10 and to add 100. Students will add 10 or 100 to a number and write the sum. They will explain how adding 10 changes the digit in the tens place and how adding 100 affects the digit in the hundreds place.

 

• Use an open number line to add hundreds and tens. Check out this video to watch this strategy.

 

• Use an open number line to add three-digit numbers. This video explains this strategy.

 

Ways to Support Math at Home

• When shopping, ask your student to add the price of 2 or 3 items to determine the total cost. Use whole-dollar amounts only. Ask your student whether a given amount is enough money to buy the items.
• Have your student be the scorekeeper when playing a game as a family. Ask what strategy he or she uses to total each player’s score. Have your student explain the strategy.
• Have your student add to find the total number of pages that he or she reads in a week. Have your student add to find the new total of pages each time he or she reads. Challenge your student to set a goal and read X number of pages that you determine for the week.

Model other scenarios, making sure to use terms such as “total,” “sum,” ”addend,” “strategy,” and “compatible numbers.”

This week in math, we will conclude Chapter 6, “Fluently Subtract within 100.” On Wednesday, we will learn about how to solve one and two-step word problems when subtracting two-digit numbers in problems that require regrouping. On Thursday, we will take the Chapter 6 Post-Test and the Chapter 7 Pretest. We will begin Chapter 7 on Friday.

In Chapter 7, “Understand Place Value to 1,000,” your child will solidify his or her understanding of place value. They will learn the value of each digit, depending on whether the digit is in the ones, tens, or hundreds place. Your child will learn to read and write numbers up to 1,000 in standard form, expanded form, and word form.

The vocabulary words for Chapter 7 are:

• Hundred
• hundreds place
• thousand
• expanded form
• standard form
• word form.

 

Our learning targets this week are:

• Solve one- and two-step word problems. Two-step word problems can be tricky because only one question is clearly asked, even though two steps are needed. Students learn to identify the given information, figure out what the problem is asking, choose a strategy, and explain how they solved it.

Example:
You have 45 marbles. You give 18 to one friend and 12 to another. How many marbles do you have left?

Step 1: 45 − 18 = 27
Step 2: 27 − 12 = 15

By breaking the problem into parts and using strategies they’ve learned, students build confidence in solving multi-step problems.

• Identify groups of tens as hundreds. Students will circle ten groups of ten, then tell how many tens and hundreds are modeled, and then write the number. For example: 20 tens, or 2 hundreds, or 200.

 

Ways to Support Math at Home

• Practice Subtraction Facts: Quick recall of basic subtraction (like 13–5 or 9–4) makes regrouping much easier. A few minutes of flashcards, card games, or saying facts aloud while driving can make a big difference.
• Talk Through Word Problems: When reading a word problem together, ask questions like, “What is the problem asking?”, “What information do we already know?”, and “What should we do first?” This helps strengthen reasoning and problem-solving skills.
• Explore Tens and Hundreds: Use everyday items like coins, pasta, or blocks to make groups of ten. Then group ten tens to make a hundred. You might say:
  “Let’s count 10 groups of 10. How many do we have altogether?”
  This hands-on practice supports understanding place value.

This week, we will continue Chapter 6, “Fluently Subtract within 100.” This chapter places a strong emphasis on regrouping with subtraction. This is what many adults know as “Borrowing.” Typically, this strategy confuses kids, so students begin by using models (blocks) and subtracting a one-digit number from a two-digit number. For example, 21-6 =?

There are no new vocabulary words for this chapter.

Our learning targets for this week are:

• Use Models to subtract a one-digit number from a two-digit number. Students will determine if regrouping is necessary when subtracting. If needed, they will trade 1 ten for 10 ones to make the subtraction possible. Then, they will subtract to find the difference.

 

• Use models to subtract a two-digit number from a two-digit number. They will first decide if regrouping is needed, and if so, they will trade 1 ten for 10 ones to help complete the subtraction. Using their model, students will then subtract and solve for the difference.

 

• Subtract a one- or two-digit number from a two-digit number. Students will first check to see if they have enough ones to subtract. If not, they will regroup by breaking apart a ten into 10 ones. After adjusting the numbers as needed, they will subtract to find the difference.

 

• Use addition to check subtraction. Students will solve a subtraction problem and use addition to check the difference.

 

Ways to Support Math at Home

• Practice Basic Addition Facts. Being able to recall single-digit addition facts quickly (for example, 7+8 or 9+6) helps students solve larger subtraction problems with more confidence. A few minutes of practice each day can make a big difference. If you'd like something easy to use at home, XtraMath is a great online tool for quick, daily fact review.Talk about the total amount of money your child has saved. Then talk about how much money will be left after spending some of it. For example, “You had $24. You spent $8 to buy a book. How many dollars do you have left? How did you find the difference?”

• Pose a problem like this: “You have $62. After buying a pair of shoes, you have $18 left. How much did the shoes cost?” Have your student explain the strategy they use to find the answer.

• Ask your student to use a store ad to determine several items with a total cost of less than $100. Have your student find how close the total is to $100. Use only whole-dollar amounts. Have your student use addition to check their subtraction.

• Model other scenarios, making sure to use terms such as “difference,” “subtract,” and “strategy.”

Math

We will conclude Chapter 5, “Fluently subtract within 10,0” this week.

On Wednesday, we will take the Chapter 5 post-test and the Chapter 6 Pre-test.

On Thursday, we will begin Chapter 6, “Fluently Add Within 100.” In this chapter, your student continues to learn and practice strategies for subtracting numbers. These strategies include using regrouping (“borrowing”), place value, and part-part-whole models. There are no new vocabulary words for this chapter.

Our learning targets for this week are:

This week’s learning goals are:

• Choose a strategy to subtract. In this lesson, students will review the strategies learned in this chapter and then choose a strategy to use when subtracting, solve the problem, and explain the strategy they used.

 

• Solve 2-Step Subtraction Problems. Two-step subtraction problems can be challenging because even though two actions happen in the problem, there is usually only one question asked at the end. To support understanding, students begin by identifying what information is given and what the question is asking. Then, they solve each step one at a time and explain the strategy they used.

Example:
You have 47 stickers. You use 15 to decorate a card, and later you give 12 to a friend.
How many stickers do you have now?

Step 1: 47 − 15 = 32 (Stickers left after decorating)
Step 2: 32 − 12 = 20 (Stickers left after giving some to a friend)

By breaking the problem into steps and thinking about what is happening in each part, students learn to apply subtraction strategies—such as using place value, using a number line, or subtracting in parts—to solve multi-step word problems with confidence.

• Use models and regrouping to subtract a one-digit number from a two-digit number. Students will decide whether regrouping is needed when subtracting. If so, they will exchange 1 ten for 10 ones to help solve the problem. They will model the subtraction and find the difference.

 

• Use Models to subtract a one-digit number from a two-digit number. Students will determine if regrouping is necessary when subtracting. If needed, they will trade 1 ten for 10 ones to make the subtraction possible. Then, they will subtract to find the difference.

 

Ways to Support Math at Home

• Practice subtracting within 100 using real objects. Use snacks, coins, Legos, etc. Have your child show the subtraction by grouping tens and ones. If regrouping is needed, have them physically trade 1 ten for 10 ones.
• Talk through 2-step word problems. Read a story problem slowly and ask:

1. 1. “What is happening first?”
   2. “What happens next?”
   3. “What is the question asking?

• Encourage clear explanation of strategies. When your child solves a subtraction problem, ask: “How did you figure that out?” This builds confidence and deepens understanding more than getting the answer quickly.
• Build fluency with basic facts.
  Help your child continue practicing single-digit addition facts (like 6+6 or 8+9). Knowing these quickly makes larger subtraction problems much easier. If you'd like extra practice, XtraMath is a simple program you can use at home.

We will be continuing the start of Chapter 5 this week, which is "Fluently Subtracting within 100." Students will be learning a variety of strategies to help them as they learn the most efficient way to subtract 2-digit numbers.

Vocabulary words and phrases used in this chapter are:

• open number line
• difference
• break apart
• subtract
• compensation

This week’s learning goals are:

• Use an open number line to subtract tens and ones. Students will use an open number line to count back by tens and ones. They will describe the patterns they notice and write the difference between the numbers.

 

• Use addition to subtract on an open number line. Students will count on from a number to a greater number and explain how this strategy can be used to subtract. They will write the difference between the two numbers.

 

• Break apart one-digit numbers to subtract. Students will break apart the number being subtracted to first reach a decade number (a number ending in zero, like 30 or 40). Then, they will subtract the remaining part to find the difference.

 

• Break apart two-digit numbers to subtract.

With the strategy, “Break Apart to Subtract,” students will break apart the number being subtracted to get to a decade number (10, 20, 30, 40, etc.). Then, students will subtract the other partner number to find the difference.

For example:

53 - 7 =?

Break the 7 into a 3+4

Subtract: 53 - 3 = 50,

        then 50 - 4 = 46.

So, 53 – 7 = 46

 

• Use compensation to subtract. Compensation to subtract is confusing to many students. You can watch this video if you are interested in learning how this strategy works.

 

Math at Home

You can practice subtraction strategies with your student using items around your home. For now, students are subtracting numbers up to 100.  Here are some activities to use:

• When baking, discuss the total number of items you baked. Then ask how many are left after your family eats some of the items. For example, say, “We baked 56 muffins. The family ate 12. How many muffins are left?”
• When cleaning out clothing items or toys, have your student create a subtraction problem to show how many items you started with and how many are left after giving some away.
• Subtract money to show how much has been spent. For example, have your student count his or her allowance or money from birthdays and holidays (whole-dollar amounts only). Then ask your student to find how much money is left after spending some of it.
• Model other scenarios, making sure to use terms such as “difference” and “subtract.”

Please help your child memorize their single-digit addition facts (for example, 6+6, 8+9, etc.). This is a critical skill for mastery by the end of 2nd grade. If you would like your child to practice at home, XtraMath is an easy way to do so.

This week, we will wrap up our unit on how to add fluently within 100. Students will take the post-test on Tuesday. Students will take a benchmark math test on Wednesday, and we will start our next unit after that.  

Our chapter 4 learning targets are:

• Solving one and two-step word problems involving 2-digit numbers. Two-step word problems continue to be a struggle for many students. The problems are broken down into two individual steps. Students continue to apply strategies they’ve learned to add two addends at each step.
  • Example: “You have 18 jellybeans and find 19 more. Your friend has 32 jellybeans. How many jellybeans do you and your friend have in all?”
    • Step 1: Me: 18 + 19 = 37 (This step is difficult for students because the question is not explicitly stated.)
    • Step 2: Me and my friend: 37 + 32 = 69

We will be starting Chapter 5 on Thursday and Friday, which is fluently subtracting within 100. Students will be learning a variety of strategies to help them as they learn the most efficient way to subtract 2-digit numbers.

Vocabulary words and phrases used in this chapter are:

• open number line
• difference
• break apart
• subtract
• compensation

This week’s chapter 5 learning goals are:

• Use an open number line to subtract tens. Students will use an open number line to count back by tens and describe the patterns they notice. They will then write the difference between the numbers. Watch this video to learn about using an open number line to subtract

• Use an open number line to subtract tens and ones. Students will use an open number line to count back by tens and ones. They will describe the patterns they notice and write the difference between the numbers.

 

Math at Home

You can practice subtraction strategies with your student using items around your home. For now, students are subtracting numbers up to 100.  Here are some activities to use:

• When baking, discuss the total number of items you baked. Then ask how many are left after your family eats some of the items. For example, say, “We baked 56 muffins. The family ate 12. How many muffins are left?”
• When cleaning out clothing items or toys, have your student create a subtraction problem to show how many items you started with and how many are left after giving some away.
• Subtract money to show how much has been spent. For example, have your student count his or her allowance or money from birthdays and holidays (whole-dollar amounts only). Then ask your student to find how much money is left after spending some of it.
• Model other scenarios, making sure to use terms such as “difference” and “subtract.”

Please help your child memorize their single-digit addition facts (for example, 6+6, 8+9, etc.). This is a critical skill for mastery by the end of 2nd grade. If you would like your child to practice at home, XtraMath is an easy way to do so.

This week, we will continue learning how to add fluently within 100. Students will be learning a variety of strategies to help them as they learn the most efficient way to add large numbers.  

Our learning targets are: 

• Use regrouping to add. Students will learn the traditional algorithm that many of us grew up knowing as, “carrying.” It is now called “regrouping.” Check out this video or this video that explains this strategy. 

• Use regrouping when needed to add. Students will use place-value to rewrite an addition problem, show 10 ones regrouped as 1 ten, then solve the addition problem. 

 

• Add two-digit numbers. Students will choose a strategy to solve and explain their strategy. 

 

• Add up to three 2-digit numbers. Students will choose two of the ones’ digits to add first, add the other one’s digit, and then add the tens to find the sum. Here is a video that shows some strategies we use.  

For example: 

   14 

   26  

+ 32  

 

We would add 4+6 in the one’s column, and that is 10. Then add the 2 to the ten and that is 12. Then we add the tens column. 10+20+30=60. Then 60+12=72 

 

Math at Home 

A great context for discussing the addition of two-digit numbers is adding whole dollar amounts of money.   

When working with amounts of money, use the following ideas.  

• Discuss the total cost of two items with your child. For example, say, “This toy costs $25 and this one costs $42. How can you find the total cost? How much do these toys cost in all?” 

• Ask your child to help you add up to 3 whole dollar amounts when shopping. Say, “This item costs $15, this one costs $9, and this one costs $35. Which two numbers will you add first? Why?” Have your student explain their thinking.  

• Help your child practice using place value to add money. Have him or her add the ones and then the tens. Ask, “How many ones are there in all? Do you need to regroup? What do you do after you regroup?” Give your student a notebook or receipt to write the numbers, draw a quick sketch if needed, and add. Help your child regroup if needed.  

• Model other scenarios, making sure to use terms such as “partial sums,” “place value,” “regroup,” and “sum.”  

Please help your child memorize their single-digit addition facts (for example, 6+6, 8+9, etc.). This is a critical skill for mastery by the end of 2nd grade. If you would like your child to practice at home, XtraMath is an easy way to do so.