Sunday, April 22, 2012

Introducing Fractions with a Story

I never get as much done on the weekends as I would like, but lately my weekends have consisted of sitting around and doing nothing, so I haven't had an excuse!

My weekend so far:
- Surprised a co-worker on her birthday (just a little surprise!)
- Went to my husband's improv show and went onstage as a volunteer (and actually did okay!)
- Went to a thirty-one purse party (not usually a purse girl, but I'm excited to get my order!)
- Tried out a new local restaurant (mmm chili on top of mac 'n cheese in a breadbowl)
- Got the chance to see some out of town friends (over frozen yogurt!)

For once, I have an excuse for not getting much done on the weekend.

Anyway, this will be a super simple post, but I wanted to share with you how I introduced fractions. I love to tell stories and incorporate the learning into it, usually with some (very) quick sketching on chart paper.

By 2nd grade, they already have some background knowledge, but even outside of 'school' fraction learning, almost every kid knows what 'half' means.


 Me: So my little brother and I were hanging out and we decided to go and get a pizza. He cut the pizza in half. (draw the blue line)
Class: What!? No! That's not fair!
Me: What do you mean? He cut the pizza into two parts...
Student: But the two parts aren't the same size!
Me: Wait, so 1/2 means two EQUAL parts? How should we have split the pizza?


(Student drew the blue line.)
Me: OHHHH. So we should have each gotten the same amount of pizza.
Class: Yessss!

Me: Okay, I get it. So then we got some breadsticks. There were four breadsticks in the order, and my brother was so nice. He gave me half of the breadsticks. (Draw the blue line.)



Class: Nooooo! That's not fair! That's not half!
Me: Wait. That isn't half? Who can tell me why?
Student: Because he got three and you only got one and that's not fair!
Me: But I thought half meant splitting something into two parts. Here's my brother's part, and here's my part. Two parts!
Student: NOOOO. The two parts have to be the SAME!
Me: So half means something has been split into two EQUAL parts. Ohhhhh. So how would I really split these in half?

  

(Student draws the blue line.)
Me: Okay, so for dessert, my brother and I went back and shared a pie with my mom. He cut the pie, and then he gave himself one part out of 3 parts. So... 1 out of 3. (Writing the fraction)
Class: NOOOOOO!!
Me: Oh no. I almost forgot. Fractions have to have a certain kind of parts. Can you help me? Fractions must have-
Class: EQUAL PARTS!
Me: So why isn't this 1/3?
Student: Because the parts aren't equal!

 

Me: So let's see. We should have split the pie into three EQUAL parts! What if we split the pie this way?
Class: YES!

 

Me: And how do you know that I got 1/3 of the pie? Whisper your answer to your neighbor.
(silent countdown) Okay, who wants to share how they knew this is 1/3?
Student: Because you got one of the pieces and the pie is in 3 equal pieces.
Me: Oooh! Oooh! Did you hear her? WHAT kind of pieces do fractions have to have?
Class: EQUAL pieces!
Me: Okay, let's write out what we've learned about fractions.

And then we made this anchor chart:


It's nothing crazy groundbreaking, but it does remind students that parts of a whole can mean a whole object OR a whole group, which is always tricky for my kids.

Afterwards, a few of my kids were very concerned that the whole pizza story with my brother really happened. At first, I think they just thought he was really mean. And when I explained that he wasn't really that mean, their concern seemed to be that maybe he just wasn't very smart and didn't understand fractions. I had to assure them that I made up the whole story, and that the only reason my brother would try to eat more breadsticks is as a joke because he likes them so much!

Hope you are having a great weekend!

6 comments:

  1. I think I'm stealing this idea to use as a fractional parts review before our fractional parts assessment this week! AWESOME!!!

    Oh My Little Classity Class

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  2. I just used this idea, changing things or course, and my kids LOVED it!! We started fractions yesterday so this was a fun review of what was taught.

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  3. I LOVE this idea of using story to teach math! I have pinned your idea to my math board :)

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  4. I LOVE this idea of using story to teach math! I have pinned your idea to my math board :)

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  5. Love this little story! Thank you for sharing your drawings, too! I always introduce equal and unequal using food and my kiddos definitely know what's fair when it comes to splitting pizzas and cookies!

    Katie :)
    KTP: Keep Teaching and Planning!

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  6. I love this story. I am a student teacher and I was searching for a fun fractions introduction, Thanks a lot.

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