The Struggle Is Over!

Tenths versus tens? Hundreds versus hundredths? Place value can be very confusing! Understanding the idea that although 1.23 has three digits, its value is less than 2.5, can be a struggle for many students. Mastering the concept of decimals and is essential for progressing through mathematics, and knowledge of decimals and percents is a necessary life skill. As adults, we compare decimals almost daily as we shop for the best deals at the grocery store, compare gas prices, and more. While it can be tricky to teach, this skill is one not to overlook. Here are eight strategies students can use when comparing decimals.

1. Base Ten Blocks

Base ten blocks offer a tactile way for learners to easily determine the greater decimal. They can very quickly see which decimal is greater by using base ten blocks and comparing. Providing them with a T-chart on which to place the blocks can help pupils keep the two decimals visually separate.

2. Hundreds Chart

Very similar to comparing decimals with base ten blocks, hundreds charts require pupils to shade in the appropriate amount for each decimal. They can then compare the decimals by determining which hundreds chart has more or less area shaded in.

3. Number Lines

A number line is another visual representation that can be beneficial when working with decimals. By placing the decimal on a number line, students can find which number is farther left or right and easily see which is greater.

4. Place Value Chart

Giving pupils a graphic organizer so they can place each digit in its appropriate spot can help learners differentiate between the values of each digit. This is especially helpful if they are struggling with numbers that do not have the same number of digits.

5. Adding Zeros

One of the most confusing things with decimals is the idea that a number can have fewer digits but greater value than a number with more digits. Teaching your class that they can add zeros after the last digit to the right of the decimal without changing the value can enable them to look past the amount of digits to differentiate the actual value of the number.

6. Aligning Decimals Vertically

Just like subtracting numbers horizontally can be extremely difficult, so can comparing decimals. Align the numbers vertically with the decimals lined up so your young mathematicians can look at the numbers from left to right to see which is greater.

7. Comparing to Money

When decimals only go to hundredths, relate instruction to money. Money is something your kids have already encountered. Without realizing it, most of them are at least familiar with place value to the hundredths. Comparing money amounts can be easier for them to comprehend at times than comparing two decimals that have no context for them. Try using play money to help class members visualize the amounts.

8. Converting to Percents

Teaching students how to turn a decimal into a percent mentally or with a calculator is another strategy you can use. Since most students encounter percents from a young age with grades or at a store, they have already learned that 75% is higher than a 63%. For many, comparing percents instead of decimals can be easier to process. One downside might be that some of your pupils will write down the percent instead of the decimal, but they will understand the concept, and with a little practice, they can correct their tendency toward this mistake. 

Now that you have these strategies to add to your tool belt when comparing decimals, what other strategies have you used to effectively teach youngsters how to compare decimals?