20 printable 1st grade math worksheets designed for Common Core learning, featuring fun addition and number value exercises.

The image you've shared is a promotional graphic for 1st Grade Math Printables by Molly Lynch, featuring two sample worksheets titled:

1. "Happy Addition"
2. "Chewing on Numbers"

These are part of a set of 20 Common Core-aligned math worksheets designed for first-grade students.

Let’s break down and solve the problems shown in each worksheet to explain the concepts and solutions.

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🌟 Worksheet 1: "Happy Addition"

Instructions:
Solve each addition problem. If the sum is odd, color the happy face yellow. If the sum is even, color the happy face pink.

#### Problems:
| Problem | Sum | Even or Odd? | Color |
|--------|-----|--------------|-------|
| 4 + 3 = 7 | 7 | Odd | Yellow |
| 9 + 1 = 10 | 10 | Even | Pink |
| 5 + 2 = 7 | 7 | Odd | Yellow |
| 6 + 4 = 10 | 10 | Even | Pink |
| 1 + 1 = 2 | 2 | Even | Pink |
| 3 + 2 = 5 | 5 | Odd | Yellow |
| 3 + 3 = 6 | 6 | Even | Pink |
| 2 + 1 = 3 | 3 | Odd | Yellow |
| 4 + 5 = 9 | 9 | Odd | Yellow |
| 3 + 6 = 9 | 9 | Odd | Yellow |
| 5 + 5 = 10 | 10 | Even | Pink |
| 4 + 4 = 8 | 8 | Even | Pink |

✔ Explanation:
- Even numbers end in 0, 2, 4, 6, or 8.
- Odd numbers end in 1, 3, 5, 7, or 9.
- Students practice addition facts (within 10) and learn to identify odd and even numbers.

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🌟 Worksheet 2: "Chewing on Numbers"

This worksheet has two parts:

#### Part A: Write the value of the underlined digit

| Number | Underlined Digit | Value |
|--------|------------------|-------|
| 56 | 5 | 50 (5 tens) |
| 81 | 8 | 80 (8 tens) |
| 24 | 4 | 4 (4 ones) |
| 17 | 1 | 10 (1 ten) |
| 23 | 3 | 3 (3 ones) |
| 92 | 2 | 2 (2 ones) |
| 35 | 3 | 30 (3 tens) |
| 105 | 0 | 0 (0 tens) |
| 62 | 2 | 2 (2 ones) |
| 49 | 9 | 9 (9 ones) |

✔ Explanation:
This teaches place value — understanding that digits in a number represent different values based on their position (tens vs. ones).

#### Part B: Write the value of the numbers

| Description | Value |
|-----------|-------|
| 5 tens and 12 ones | 50 + 12 = 62 |
| 9 tens and 3 ones | 90 + 3 = 93 |
| 3 tens and 15 ones | 30 + 15 = 45 |
| 8 tens and 5 ones | 80 + 5 = 85 |
| 2 tens and 22 ones | 20 + 22 = 42 ✘ Wait! But the answer is written as 32? That's incorrect. |

⚠️ Error in the worksheet?
Let’s check:
- 2 tens = 20
- 22 ones = 22
- Total = 20 + 22 = 42

But the student wrote 32, which is wrong.

✔ Correct Answer: 42

➡️ So, this appears to be a mistake in the student’s work, not in the worksheet instruction.

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✔ Summary of Concepts Covered

1. Addition within 10 – Basic facts
2. Odd and Even Numbers – Recognizing patterns
3. Place Value – Tens and ones
4. Expanded Form – Writing numbers from tens and ones

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📚 Educational Standards (Common Core)

These worksheets align with 1st Grade Common Core Standards, such as:

- 1.OA.C.6 – Add and subtract within 20.
- 1.NBT.B.2 – Understand that the two digits of a two-digit number represent amounts of tens and ones.
- 1.NBT.B.3 – Compare two two-digit numbers based on meanings of the tens and ones digits.
- 1.OA.C.5 – Relate counting to addition and subtraction.

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🔍 Final Thoughts

This is an engaging, colorful, and educational resource for first graders. The worksheets use fun themes (happy faces, chewing gum) to make learning enjoyable.

✔ Correct Answers Recap:
- All addition sums are correct.
- Place value answers are mostly correct except 2 tens and 22 ones = 42, not 32.

> 💡 Tip for Teachers/Parents: Review the last problem with students to reinforce that 22 ones = 2 tens and 2 ones → so total is 2 tens + 2 tens + 2 ones = 4 tens + 2 ones = 42.

Would you like me to generate a corrected version of this worksheet or create similar problems?