Operations With Decimals and Powers of Ten: Tips and Tricks
- In the classroom, display a large copy of the place-value chart shown below. This will help students memorize the names of the places.
- Remind students that the names of the decimal numbers end in th. They can practice by identifying and saying “hundreds and hundredths,” “thousands and thousandths,” “tens and tenths.”
- Remind students of the meaning of these mathematical symbols.
- To learn how to round whole numbers and decimals, it is important to know all the place-value positions on the chart.
- When students compare decimals, remind them that they can always add zeros to the right of a decimal number without changing its value. For example, they might find it easier to compare 0.82 and 0.823 if they rewrite 0.82 as 0.820.
- A common mistake when adding decimals is misplacing the decimal point in the sum.
Show students models for this problem.
- Remind students to keep decimal points lined up and to add in columns.
- You can reinforce the meaning of multiplication by modeling a problem as repeated addition.
- Have students make the connection between the word and and the decimal point when saying decimals. 6.09 should be read “six and nine hundredths,” not “six point zero nine.”