Simple Fraction Addition Stories
Lesson 7 of 9
Objective: SWBAT represent simple addition stories involving fractions on a number line and explain their reasoning.
Some students have not had the experience of acting out (as in a miniature skit) word problems before, so I guide them through a few examples. Here’s how it goes:
“Jose and Zahory come on up.”
I briefly take Jose and Zahory aside, an act which in itself piques the interest of the class, and tell them that they will act out their part of the story.
I draw a number line on the board with a zero on the left and a 1 on the right. I divide it into eighths but don’t label them.
“Zahory is really hungry after soccer practice and when she sits down to dinner, she eats 5/8 of a pizza. That’s right! Five pieces. Broccoli pizza, her favorite.”
Zahory pretends to eat the pizza. I make commentary like a newscaster. “Wow! Who knew she was this hungry! That must have been a really intense soccer practice! There won’t be any left for her brother. In fact, there might not be any pizza left in Tucson! It’s incredible!”
I draw and arrow that jumps from 0 to 5/8 on the number line.
Now Jose shows up at her house. She forgot she invited him over for dinner! He is afraid of broccoli, for some reason. (Jose acts out picking up a pizza and then being frightened by it.) Eventually he eats a piece, because he’s really hungry, but it scares him.” (Jose anxiously eats the piece of imaginary pizza). Using a different colored marker, I jump 1/8 on the number line.
Below the number line, I write 5/8 + 1/8 = and then I say,
“How many pieces of delicious, nutritious…well, sort of… broccoli pizza did Jose and Zahory eat in all?”
The students say “6/8” and I write it and put a star at the end point on the number line.
There is a fine line between being too silly and enjoying acting out stories in a way that enriches learning. As I tend to often find strange things very humorous, I usually end up presenting myself with an opportunity to say, “Okay, what ---- just did was super funny, but I need to refocus now.” Then I do. Students get that. They learn that they can laugh and have fun and enjoy strange little humorous moments without getting off topic, and they also know that if they do get off track, I will redirect them, or, as a last resort, I become The Serious Teacher. Then, with a straight face and neutral voice, I run them through as dull a problem as I can think of… “This is a piece of paper. It is divided into fourths. I gave ¼ to Omar. I gave ¼ to Yaria (I draw it). How many fourths did I give away?” This usually refocuses them quite quickly.
I use this method because it’s naturally engaging, and children learn best when they are enjoying something. Equally important, it provides them with visual and (in the case of the actors) kinesthetic cues for the benchmark fractions. Finally, it’s an activity in which everyone, regardless of ability, can participate because as the “script writer” I can subtly manipulate the roles so that they work for each child.
After they have acted out at least 3 examples, I turn it over to the them and a team of students create and act out a simple fraction story. The only thing I give them is the equation.
Students write 3-10 simple fraction word problems in which they are adding fractions. I give all students the equations they need to use and for some students I provide fraction word story sentence frames.
I have sentence frames and verb/noun list for several reasons. Some students become overwhelmed with the idea of writing. They say they can't think of a noun/verb so I avoid that issue by providing them with some of they can't think of their own. Also, they are still working with sentence structure, especially the English language learners, so providing this simple frame helps them keep the words in order. I want the the sentence writing process to interfere with their ability to think about the math and providing a format for students who need it enables them to move forward. I also work to incorporate basic language skills into all subject areas, and math is no exception.
I randomly choose three students to present one of their word problems using the document camera. As a class we look for clarity, what is the problem asking, what is the equation we need to solve, and how would this be represented on a number line.