Understanding how our ten number system works enables students to see interesting and useful patterns and relationships in these math activities. These patterns allow students to develop more efficient mental math strategies when multiplying by multiples of 10 or 100. Students will also review rounding and apply this skill to larger numbers - up to 100,000’s place.

Multiplication is essentially repeated addition, or growing numbers by doubling, tripling, quadrupling, and so on. This unit presents mental models and strategies that help students learn and review the concept of multiplication. Students explore multiplication using arrays, partial products, doubling methods and the standard algorithm to solve numerical and word problems. Students will multiply whole numbers and simple decimals by base ten exponents (i.e. .3 x 103).

Subtraction fluency within 20 is the focus of this guided lesson for second graders. Kids will be tasked with mental subtraction, as well as with using manipulatives and drawings to add and subtract larger numbers. Word problems will help to round out the lesson, as kids follow the step-by-step method of solving subtraction word problems. For even more practice in this skill, check out our subtraction worksheets.