Hamilton's Math Update 11-4-2024
This week, we will continue with chapter 5, subtracting numbers within 20.
In this chapter, your student will be subtracting with numbers greater than 10. The strategies counting back and using addition to subtract will be used again. The subtraction strategy get to 10 will be introduced to your student as well.
There are many situations at home that you can use to practice subtraction. Meal and snack times present many opportunities. Keep in mind that the maximum number of objects your student will work with in this chapter is 20.
While sharing a meal or snack, use the following activities.
- Give your student a number of items, such as raisins. Ask how many there are. Then say, “Suppose you plan to eat 9 of the raisins. How can you count back to find how many raisins will be left? How can you use a related addition equation?”
- Cut 2 cups off 2 egg cartons so that each carton has 10 cups. Count out 16 grapes and have your child place 1 grape per cup to fill 1 egg carton and use as many cups as needed of the second carton. Say that you plan to eat 8 grapes. Use the get to 10 strategy to find the number of grapes left: Get from 16 to 10 by subtracting 6. Model this by removing the 6 grapes from the second carton. Because 8 = 6 + 2, you still need to subtract 2 from the 10. Model this by removing 2 grapes from the first carton. Have your child explain each step as it is completed.
- Review making true addition or subtraction equations by giving yourself several items and giving your child fewer of the items. Ask, “How many more do you need so that we both have the same amount?” Then repeat the activity, giving your child more than you have. Ask, “How many do you need to take away so that we have the same amount?”
By the end of this chapter, your student should feel confident with the learning targets and success criteria on the next page. Encourage your student to think of other ways to model and practice subtraction strategies.
Have a great time snacking and subtracting together!