3 Steps to Converting Fractions to Decimals Conceptually
Teaching students to understand how to convert a fraction to decimals seems like an impossible task to many 6th and 7th grade math teachers. Math teachers in elementary school usually teach students using fraction wheels for fractions and decimals grids for for decimals, however I have never seen them apply fraction concepts to decimal grids. This seems to be where their understanding of decimals reaches its end point. When I taught 6th grade math I always explained to my students that a fraction can be converted to a decimal because they are both a part of a whole. I’m sure this didn’t make any sense to them because I know that most students struggle with fraction concepts. There are 3 steps that teachers can take to teach their students to convert fractions to decimals using decimal grids. 1. Teach the math vocabulary –Teaching essential vocabulary such as terminating and repeating decimals will help the students differentiate between terminating fractions and repeating fractions. For example 1/8 is a terminating fraction because when a decimal grid is divide by 8 it will divide evenly in the thousandths place. 2. Convert fractions that will terminate as decimals– Before teaching the students how to convert repeating decimals using a decimal model common fractions such as 1/4, 3/4, and 2/5. These fractions can easily be converted to decimals using a decimal grid and will help the students understand the concept. Once the students are comfortable with the idea of how fractions are converted to decimals then fractions like 1/8, and 1/3 can be used to extend the students understanding of converting fractions to decimals using decimal grids.
3. Identify fractions that will not repeat before converting – Identifying fractions that will repeat before converting a fraction to a decimal will keep students from performing unnecessary calculations. For example, the fraction 1/8 has a denominator of 8 if you divide a decimal grind into 8 groups of tenths, 8 groups of hundredths this shows how the denominator 8 divides evenly in the tenths and hundredths place. After this is done there are 4 hundredths left over which seems impossible because the hundredths place has already been calculated. The last 4 hundredths must be converted to thousandths so that they thousandths can be divided by 8. If a student is able to identify denominators that will not repeat it will help the process of converting fractions to decimals seem less labor intensive.
Converting fractions to decimals can be scary for many students because the process is very abstract to them. If the students understand the process conceptually then it can serve as the foundation for connecting other mathematical concepts.