standard_description: Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
problem_activity: Complete the following chart:
| **           Standard Form          ** | **           Word Form          ** |                          **           Expanded Form          **                          |
|----------------------------------------|------------------------------------|------------------------------------------------------------------------------------------|
|                                        |                                    | $$(4\times1)+\left(6\times\frac{1}{100}\right) + \left(3\times{\frac{1}{1,000}}\right)$$ |
|                                        |      thirty-five thousandths       |                                                                                          |
|                 42.905                 |                                    |                                                                                          |


aligns: no