Wednesday, March 27, 2013

#Slice 2013: 27 of 31- A Decimal Story

During the month of March, I am participating in the Slice Challenge, hosted at

My fifth-grade daughter struggles to make sense of mathematical concepts, but she is a strong reader and writer. I have been reading Jim Knight's book, High Impact Instruction, and his chapter about stories resonates with me. He wrote that stories have the power to help people remember information. Since then, I have been re-thinking some math stories that I worked on last year. I wrote this story tonight because Cecily was having such a hard time understanding the concept that zeros after a decimal number don't change the value of the number. For example, .9 is equal in value to .900000.  I am wondering about the value of stories for teaching some of our students who have strong verbal skills, but struggle with understanding or remembering increasingly abstract mathematical concepts.

NT Learns His Value

Once upon a time there was a one digit decimal, .9. Nine-tenths, otherwise known as NT to the other numbers was mostly happy. He was included in many fact challenges and word problems and, even though he didn’t understand why, most students were really happy to see him show up on their papers. Definitely, .95 and .99 seemed to make students happier, but they were okay with .9, as well. This made no sense to NT and NT didn’t participate in many of the games that numbers play with each other because he felt smaller than so many of the other numbers.

NT would sit to the side and watch .89 play volleyball math against .851 and .1234. He wished that he were like them; they were so big with all of their numbers. NT wished that he could have more numbers like they did because he always felt so small around them. Sometimes, they would invite him in to play but he never said yes.

“They are all so much bigger than I am,” he always thought to himself.

One day, .333 came and sat down next to him. .333 always intrigued NT because he was a repeating decimal and his numbers went on forever. (But that’s another story.)

“We’re going to play a soccer game,” .333 said. “Why don’t you join us?

NT shook his head. He wanted .333 to go play so that he could just watch and feel small.

But, .33 stayed around. “Seriously, why don’t you ever play in the number games?”

NT debated and then decided to tell .333 the truth. “I wish that I had more numbers like the rest of you. You are all so big and I am so small.”

NT didn’t understand when .333 started laughing, but then .333 spoke. “Silly number,” .33 said. “You are bigger than almost all of the rest of the decimal numbers.”

NT didn’t understand.

“Just give yourself as many zeros as you want,” .33 said. “You can be .90 or .900 or .9000! You are way bigger than I am and even bigger than .89!”

“I can do that?” NT couldn’t believe it. Was he really bigger than the other decimals? All he had to do was add zeros? “What if  .89 adds a zero, though?” he asked.

.33 laughed again. “Then you add a zero, silly. If he is .890, then you are .900, and you are still bigger. You make it be that you have the same number of places after the decimal point and then you can truly compare numbers. Now, c’mon, come play.”

NT got up and followed .333 on to the field to join the number games and he never felt smaller than any number that started with an 8 after the decimal place again.

I'd love feedback or ideas for more personified numbers!


  1. What a clever way to explain a difficult concept! :)

  2. Now that is a story you should publish. Putting difficult concepts into a format that uses our diverse strengths is a great idea! LOTS Of us are stronger in the linguistic area~

  3. I'd like to try it on someone! When I get back to school, I'll share it to see if it's helpful. I agree that stories help concepts come alive, and also "stick". What a good idea, Melanie. I think that some of the work Marilyn Burns does relies on stories, too.

  4. Did this help your daughter? I think it would have helped me to understand when I was younger. Cute story! You are a story teller!

  5. Great story...narrative really helps our kids "get" concepts in math, even I'd think with much older kids.

  6. I am with Anita; you should publish this story! If it is okay with you, I will be sharing it with our math teachers.

    1. Of course--it's fine. I'm thinking about others.

  7. This is such a great idea. I love the nickname NT for the character! I hope the story helped your daughter.