standard_description: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.
problem_activity: Problem 1
Find the following products.
a.   20 × 4
b.   9 × 300
c.   5 × 6,000
Problem 2
Estimate the following products.
a.   8 × 84
b.   458 × 4
c.   2 × 9,340


aligns: no