**Curriculum – **Number Sense and Numeration

Grade 1

Solve problems involving the addition and subtraction of single-digit whole numbers, using a variety of mental strategies (e.g., one more than, one less than, counting on, counting back, doubles).

**Context**

Educator working with a small group of 4 children at a table.

**Materials**

- 1 egg cartons per student (size: holds 12 eggs)
- Marker
- 2 small game tokens per student (e.g., beans, pennies)
- 1 die per student
- Lined papers or math notebooks
- Pencils

**Summary**

Children are presented with an egg carton with numbers from 1 to 9 written inside. Children will shake the egg carton so that the game tokens will land on two numbers. They will then roll a die to determine whether they will be performing addition or subtraction. Using the two numbers and the chosen operation, children will create an equation and solve it.

**Instructions**

- Open up the egg carton and using a marker, write a number from 1 to 9 on the bottom of each rounded space. Choose three numbers to be written down twice to fill all twelve spaces. Numbers can be written in a random order. Repeat this step to create three more egg cartons.
- Hand out an egg carton, two game tokens, and a die to each child and tell them we will be playing a game to practice addition and subtraction.
- Explain to the children that they will put the two game tokens inside the carton, close the lid and “scramble the eggs” by shaking the carton. Once they finish shaking the carton, tell them to set it on the table.
- Instruct children to then roll their die to determine whether they will be adding or subtracting in this round. Let them know that rolling an even number means that they will add and rolling an odd number means that they will subtract.
- Ask children to open the lid of the carton and see which spaces the two tokens fell into. Have them create a math equation using the two numbers and the chosen operation and then solve it. For example, if the child rolled a 4 (even = addition) and the child’s tokens landed in the 7 and 3 spaces, the child can make the equation “7 + 3 = 10” or “3 + 7 = 10”. Instruct children to write their equation down on their sheet of paper or notebook.
- Tell children they can move onto the next round when they are ready by repeating steps 3 to 5. The game ends after ten rounds.

*For children who are just beginning to solve equations, teachers can first ask students to play the game using one operation. As students become more familiar with the game (or with older grades), bigger numbers can be written inside the egg carton or new operations can be introduced (multiplication/division)*

**Questions to Extend Student’s Thinking**

- How did you solve your equation?
- Do you find that certain numbers make it easier to find the answer?
- Can you tell me something about the two numbers that the tokens landed on?

**Look Fors**

- What strategies does the child use to solve the equations? Do they count up, count on, or find the answer through retrieval? Do children recognize certain math strategies? For example, do they recognize the different ways to make the number 10 or know the doubles fact to help them solve equations faster? Griffin (2003) states that as children develop stronger number sense and computation abilities, the strategy they employ will also become more sophisticated (instead of counting up, children may use counting on or retrieval).
- Do children demonstrate the ability to manipulate a mental number line? This activity requires children to solve equations without using any concrete objects. According to Griffin (2005), a major learning stage occurs when children are able to solve addition and subtraction questions in their minds by manipulating their “mental counting line structure” forwards and backwards.
- Do children use appropriate math language? Are they using words such as “sum”, “difference”, “bigger than”, “smaller than” when you ask them questions? During the activity, talk with the children and ask them to verbalize their thoughts or talk about the numbers to listen to their vocabulary.

#### References

Griffin, S. (2005). Fostering the development of wholenumber sense: Teaching mathematics in the primary grades. In M. S. Donovan & J. D. Bransford (Eds.), How students learn: History, mathematics and science in the classroom (pp. 257308). Washington, DC: The National Academies Press.

Griffin, S. (2003). Laying the foundations for computational fluency in early childhood. Teaching Children Mathematics, 9(6), 306309.

Hoffman, V. (2012, October 16). “Scrambled Egg” math. Retrieved from http://www.education.com/activity/article/scrambled_egg_first_grade_math/