unit 4 parent letter

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Place Value Flocabulary 
*Log into Classlink.
*Open "Flocabulary" app.
*Then, click the above link.​​

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regrouping

​​What is regrouping? 
When you have too many (or not enough) of one type of block, you trade it for 1 block of the equivalent value. 

​Examples for Addition
- Trade 10 units (ones) for 1 rod (ten).
- Trade 10 rods (tens) for 1 flat (hundred).
- Trade 10 flats (hundreds) for 1 cube (thousand).

Examples for Subtraction
- Trade 1 cube (thousand) for 10 flats (hundreds).
- Trade 1 flat (hundred) for 10 rods (tens).
​- Trade 1 rod (ten) for 10 units (ones).

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Addition strategies

When adding, it is best to use one of these three strategies -
- Base Ten Model
- Expanded Form 
​- Open Number Line

Strategy 1: Base Ten Model
​Use base ten blocks to model and regroup, when needed.

Strategy 2: Expanded Form 
​When adding numbers by place value (using expanded form), you add the ones first, then tens, and lastly hundreds (if it is a 3-digit number). Regroup, if needed, as shown to the right.

​Strategy 3: Open Number Line

- Start at the higher/est of the numbers in the addition problem.
- Use one of the strategies to the left to help you get to your answer.

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Subtraction strategies

When subtracting, it is best to use one of these three strategies -
- Base Ten Model
- Expanded Form (if the problem doesn't involve regrouping)
​- Open Number Line

​Strategy 1: Base Ten Model
​Use base ten blocks to model and regroup, when needed.

Strategy 2: Expanded Form 
​When subtracting numbers by place value (using expanded form), you subtract the ones first, then tens, and lastly hundreds (if it is a 3-digit number). 

Strategy 3: Open Number Line

- Start at the lower/est number at the BEGINNING of the open number line and count UP (Number Line Liam).
- Start at the higher/est number at the END of the open number line and count BACK (Jump, Hop, Step)