This spelling worksheet challenges students to unscramble mixed-up words like "mbri" and "cbu" by using the provided word bank at the bottom.

Problem Description:

The task is to unscramble the given sets of letters and write the correct words in the provided boxes. Each letter goes into one box. The words are taken from a list of spelling words provided at the bottom of the image.

Solution Approach:

1. Identify the Scrambled Words: The scrambled words are listed on the left side (e.g., "mbri", "cbu", etc.).
2. Match with the Word List: Compare each scrambled word with the list of spelling words provided at the bottom (e.g., "sack", "fed", "slap", etc.).
3. Unscramble and Write: Rearrange the letters of each scrambled word to form a valid word from the list, and write it in the corresponding boxes.

Step-by-Step Solution:

#### Scrambled Words and Their Solutions:
1. mbri → brim
2. cbu → cub
3. ckod → dock
4. oth → hot
5. fde → fed
6. dsan → sand
7. turck → truck
8. cksa → sack
9. flit → lift
10. plas → slap
11. stet → test
12. bia → lab
13. tar → rat
14. elf → elf
15. ew → we

#### Writing the Words in the Boxes:
- For each scrambled word, write the unscrambled word in the corresponding boxes, one letter per box.

Final Answer:

Here is the completed solution:

| Scrambled | Unscrambled | Boxes |
|-----------|-------------|-------|
| 1. mbri | brim | b r i m |
| 2. cbu | cub | c u b |
| 3. ckod | dock | d o c k |
| 4. oth | hot | h o t |
| 5. fde | fed | f e d |
| 6. dsan | sand | s a n d |
| 7. turck | truck | t r u c k |
| 8. cksa | sack | s a c k |
| 9. flit | lift | l i f t |
| 10. plas | slap | s l a p |
| 11. stet | test | t e s t |
| 12. bia | lab | l a b |
| 13. tar | rat | r a t |
| 14. elf | elf | e l f |
| 15. ew | we | w e |

Explanation:

- Each scrambled word was matched with a word from the provided list.
- The letters were rearranged to form the correct word.
- The words were written in the boxes, ensuring one letter per box.

This completes the task. If you have any further questions, feel free to ask!

Final Answer:
\boxed{
\begin{array}{lll}
1. & \text{brim} & b \ r \ i \ m \\
2. & \text{cub} & c \ u \ b \\
3. & \text{dock} & d \ o \ c \ k \\
4. & \text{hot} & h \ o \ t \\
5. & \text{fed} & f \ e \ d \\
6. & \text{sand} & s \ a \ n \ d \\
7. & \text{truck} & t \ r \ u \ c \ k \\
8. & \text{sack} & s \ a \ c \ k \\
9. & \text{lift} & l \ i \ f \ t \\
10. & \text{slap} & s \ l \ a \ p \\
11. & \text{test} & t \ e \ s \ t \\
12. & \text{lab} & l \ a \ b \\
13. & \text{rat} & r \ a \ t \\
14. & \text{elf} & e \ l \ f \\
15. & \text{we} & w \ e \\
\end{array}
}