# 2.2 - Skip Counting

The student will

a)  count forward by twos, fives, and tens to 120, starting at various multiples of 2, 5, or 10;

b)  count backward by tens from 120; and

c)  use objects to determine whether a number is even or odd.

### BIG IDEAS

 So that I can round numbers to get  a close, easy-to-use number when the exact number is not neededSo that I can group numbers and count by groups to get to larger numbers So that I can understand that if I can count by 10, I can more easily round numbers and understand place value

### UNDERSTANDING THE STANDARD

• Collections of objects can be grouped and skip counting can be used to count the collection.

• The patterns developed as a result of grouping and/or skip counting are precursors for recognizing numeric patterns, functional relationships, concepts underlying money, and telling time. Powerful models for developing these concepts include counters, number charts (e.g., hundreds charts, 120 charts, 200 charts, etc.) and calculators.

• Skip counting by fives lays the foundation for reading a clock to the nearest five minutes and counting nickels.

• Skip counting by tens lays the foundation for use of place value and counting dimes.

• Calculators can be used to display the numeric patterns resulting from skip counting. Use the constant feature of the four-function calculator to display the numbers in the sequence when skip counting by that constant.

• Odd and even numbers can be explored in different ways (e.g., dividing collections of objects into two equal groups or pairing objects).  When pairing objects, the number of objects is even when each object has a pair or partner.  When an object is left over, or does not have a pair, then the number is odd.

### ESSENTIALS

The student will use problem solving, mathematical communication, mathematical reasoning, connections, and representations to

• Determine patterns created by counting by twos, fives, and tens to 120 on number charts. (a)

• Describe patterns in skip counting and use those patterns to predict the next number in the counting sequence. (a)

• Skip count by twos, fives, and tens to 120 from various multiples of 2, 5 or 10, using manipulatives, a hundred chart, mental mathematics, a calculator, and/or paper and pencil. (a)

• Skip count by two to 120 starting from any multiple of 2. (a)

• Skip count by five to 120 starting at any multiple of 5. (a)

• Skip count by 10 to 120 starting at any multiple of 10. (a)

• Count backward by 10 from 120. (b)

• Use objects to determine whether a number is even or odd (e.g., dividing collections of objects into two equal groups or pairing objects). (c)

### KEY VOCABULARY

Updated: Aug 22, 2018