My fifth graders are learning how to multiplying fractions by whole numbers. I know some of you may be thinking, "Wow, I didn't learn that until middle school!" I know! I didn't multiply fractions in fifth grade either! But, the truth is, it's actually an easier concept to grasp than you may be thinking... because we use models to represent it!
When I was in school, I know that I learned to multiply fractions by making sure both of the numbers were fractions (so if there was a whole number, put it over 1) and then multiply your numerators, then your denominators and that was your answer. Of course, if you came up with an improper fraction you then had to change it to a mixed number or be sure that your fractions were simplified. I merely memorized these steps and therefore I was pretty successful while multiplying fractions. But, I had no idea what it all meant and what it looked like… until I started teaching.
When we began the unit- I introduced it with fraction circles since they are the most concrete representation of fractions. The students have been using fraction circles for years and I like how you can use the colors to represent each separate fraction and then show how they come together to create the product.
Then we moved on to actually representing the visual models with paper and pencil instead of manipulatives. I still wanted them to keep the colors so they could see where each fraction came from to create the end product.
There are many different strategies and models to represent this concept. One of my favorites is on a number line. The reason why I like this strategy the best is because it helps students to see fractions on a number line- which is one of the most common places they will use them in real life- measurement! I tend to see students struggle with reading a ruler or a meter stick, even in 5th, 6th, 7th grade. Also, the need for changing improper fractions to mixed numbers or simplifying fractions is eliminated.
Feel free to copy my anchor chart. During group, my students and I created it together. They have one for their notebook and I have this one hanging in the room for them to reference. Also, check out the task cards I created for this standard.