In this unit we study decimals and all decimal arithmetic on the 6th grade level.
The first lesson has to do with place value and comparing decimals, up to six decimal digits. The lessons in the book go through the topics of adding and subtracting decimals, rounding decimals, multiplying and dividing decimals, problem solving, and fractions and decimals. Many of these topics are actually review from 5th grade, but as we all realize, students need review. This time, they also study these topics with decimals that have more decimal digits (up to 6).
Some lessons also include exercises about evaluating expressions or solving simple equations that involve decimals, as these are topics included in the 6th grade curriculum.
The last topic in the book is dividing decimals by decimals. I explain the principle behind the shortcut ("Move the decimal point in both the divisor and the dividend enough steps so that the divisor becomes a whole number"). The principle behind this shortcut is that when you multiply the divisor and the dividend by the same number (any number), the value of the quotient does not change. This ties in even with equivalent fractions. Many school books never explain this principle in connection with decimal division.
The unit ends in a comprehensive review lesson.
I wish you success in teaching math!
Maria Miller, the author