Comparing Numbers Background Information for Teachers, Parents and Caregivers
This page provides information to support educators and families in teaching K-3 students about [topic]. It is designed to complement the Comparing Numbers topic page on BrainPOP Jr.
When your children practice comparing numbers, they develop number sense and build number relationships. We recommend using plenty of counters, base-ten blocks, number lines, hundred charts, and place value charts to help them understand how numbers are ordered. In math, an inequality is a statement about the relative size or order of two objects, numbers, or values. Introduce your children to the three basic symbols used in inequalities: greater than (>), less than (<), and equal to (=).
Show your class two small groups of cubes, pennies, or other small objects and ask them which group has the greater number. Explain that in math the word “greater” usually means “more”. Draw or show a number line from 0 to 10 to your children and pick a number, such as 4. Ask them to pick a number on the number line that is greater than 4. Children should pick 5, 6, 7, 8, 9, or 10. Explain that since these numbers come after 4 on a number line, they are larger or greater. Have children practice writing or saying a statement using the term “greater than.” For example, a student might say that “5 is greater than 4.” Try the activity again using a hundred chart and broadening the range of numbers they can choose. Review with your children that > is the greater than sign. Have them rewrite their sentences using the symbol, as in “5 > 4”. The wider part of the symbol faces the bigger number. Repeat these same activities, starting with the number line, to introduce the symbol for “less than”. Show your students that the corner, or point, of the symbol faces the smaller number.
Many children become confused with the direction the greater than and less than signs should face. It is helpful for many children to imagine that the symbol is a mouth of a hungry alligator or duck. It always wants to eat the bigger number! Have children practice writing different inequalities using the symbols. Point out how if you reverse the positions of a number in an inequality, the sign reverses direction too, as in 3 < 4 and 4 > 3.
Together, create a number sentence, such as 2 + 3 = 5. Point out the equal sign and remind them that the equal sign means that the values on either side are equal, or the same. You may want to use counters to demonstrate that a group of 2 and a group of 3 have the same number of counters in all as a group of 5, and show the corresponding number sentence on a chart. Both sides of the equal sign are the same value. Pick a number on a number line or hundred chart and ask them what number is equal.
When children must compare larger numbers that are two or three digits long, they should look at the highest place value. So 138 is greater than 41 because 138 has one hundred while 41 has no hundred. If numbers have the same number of places, children should compare the highest and then go down by place to compare the numbers. So while 245 and 238 both have two hundreds, 245 has four tens while 238 only has three tens. Therefore, 245 is greater than 238. Remind them to look carefully and make sure they compare the same place values in each number. For example, just because 245 has more tens than 327, doesn’t mean that it is a larger number.
Expose your children to number lines and hundred charts and give them plenty of manipulatives so they can have hands-on experience working with numbers. Concrete examples help children develop strong number sense and allow them to see patterns and understand how numbers are connected.