Math Background

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.
    place-value chart
  • 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.
    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.
    addition problem

    Show students models for this problem.

    model
  • 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.
    model
  • 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.”

Houghton Mifflin Math Grade 6