Week 20: Add and subtract decimals

Skills and concepts for Add and subtract decimals.

1. 1. Estimate sums and differences of decimals using rounding
2. 2. Estimate sums and differences of decimals using benchmarks
3. 3. Choose decimals with a particular sum or difference
4. 4. Complete the decimal addition or subtraction sentence
5. 5. Compare sums and differences of decimals
6. 6. Number Sequences Involving Decimals