Parent Support for K-5 Math

Second Grade Mathematics

Unit 2: Place Value Understanding

What will your child learn in Unit 2?

In Unit 2, second graders will review place value concepts they learned in first grade. Instruction will focus on place value to 100. Students will decompose a two-digit number into tens and ones. For example, 54 can be decomposed into 5 tens and 4 ones. They will understand 10 as a bundle of ten ones. Second graders will be expected to write and represent the numbers many different ways. See a sample chart below.

Additionally, students will practice counting by ones, fives, and tens to 100. Students will identify patterns in a hundreds chart and number line in order to use these math tools to practice skip counting and adding numbers. They will explore even and odd numbers. Second graders will use models and place value understanding to compare two-digit numbers.

Furthermore, students will tell and write time to the five minutes along with counting money involving half-dollars, quarters, dimes, nickels, and pennies.

What math tools and models will your child use in Unit 2?

Students will be introduced to a variety of models in second grade to support place value understanding. The type of the model depends on the student’s understanding of a ten. The handout below gives an explanation of the different types of models to represent numbers. It also includes how to use the Hundreds Chart and the Number Line to skip count by tens.

How can you support your child at home to reinforce the concepts taught in Unit 2?

There are several ways to have your child practice the math concepts at home. Try the following activities:

• Give your child a hundreds chart. Have him or her practice skip counting by tens from different starting points. (For example, start at 27 and skip count by tens.) You can also create hundred chart puzzles by cutting it apart along the lines into different number of pieces. Have your child reassemble the hundreds chart in correct order.
• Use a calculator to practice skip counting by tens. Enter a two-digit number in the calculator. Hit “+ 10” and then “=”. Keep pressing the “=” sign to count by tens. Hit “-10“ to practice counting backwards by tens.
• Visit Number Pieces to represent numbers in different ways using place value blocks. Have students represent Click the “i” on the bottom of the website for instructions on how to use it.
• Visit Grouping and Grazing to help your child make groups of ten.
• Visit Guess the Number to have your child practice comparing numbers.
• Visit Hundred Square. This online tool allows you to hide numbers behind opaque screens as well as highlight particular numbers or patterns using transparent colored screens. You can also change the increments between numbers to explore skip counting patterns.
• Visit Coin Box to help your child practice counting and exchanging coins.
• Visit Money Pieces to help your child visualize and understand money values and relationships. Click the “i” on the bottom of the website for instructions on how to use it.
• Math Games for Home: Print the handouts to practice concepts through games.