Adding and Subtracting Decimals - Grade 4
Most children know about decimals through their association with money. Even if they don't understand that a dime is 10% of a dollar and a penny is 1%, they still know how much it will take to purchase a candy bar. See Full Product Description.
Most children know about decimals through their association with money. Even if they don't understand that a dime is 10% of a dollar and a penny is 1%, they still know how much it will take to purchase a candy bar. Adding and subtracting decimals is really quite easy if you teach students only one little trick. Make the decimal points line up in a vertical row. When you are demonstrating how to add decimals, be sure to make them really large and exaggerated, or write them with a different colored marker to make them stand out.
Please see below for a selection of Leveled Lessons for Below Level (basic), and/or On Level (median), and/or Above Level (competent) readers.
Have students practice writing decimal problems on their papers and including a decimal below the addition line. Start with easy problems like .27 + .45. Then work up to tricky problems like 2.75 + .9. Be sure to use every combination of decimals including some whole numbers, some zeros and some tenths, hundredths and thousandths.
At this point, students do not need to actually do the actual addition and subtraction, as the computation is done in the conventional way just as soon as the decimal points are established. You are just trying to make sure they know how to write the problem on their papers. When they do start doing the computation, it may be helpful for them to add zeros everywhere there is a blank space: 2.75 + 0.90.