Thursday, October 24, 2013

Scientific Notation and the National Debt

Today was one of those great days I want every day to be like.  We have been working on scientific notation in 8th grade and we've learned to add, subtract, multiply and divide.  I wanted to do an activity to pull it together and let them get some practice with their new skills.  I found some good activities around the web, but nothing truly jumped out at me.  Then I somehow I started thinking about the 17 trillion dollar national debt. I thought this might be something that would catch their attention since they weren't too impressed with bacteria or the distance or mass of planets.  
So we started off with a little video to get an idea about just how much money we're going to be talking about.  I ended up showing them this one: 
I was pretty blown away by the size of the money myself!
When that video was made the total was 16 trillion.  We talked a little about the debt, and they were totally interested. They had a ton of questions!  Mostly asking why do we owe so much, what happens if we don't pay it, will we ever pay it off.  A lot of kids think that if we don't pay it off other countries are either going to bomb us or buy the country and take over.
Then I showed them this on the board: 
I messed up a little because I thought they were born in 2001 but most were born in 2000.  It was close enough though.  I had them think about and write down what they noticed and wondered about the information.  I had questions written down that I wished they would ask but I didn't say anything and let them think.  
My first class totally caught on and asked great questions:
Can we round the number and use scientific notation to make calculations easier?
How much is the debt per person?
How many times greater is the debt today compared to 2001?
What is the difference in the debt between 2013 and 2001?
How much has it grown per year?

We had about 5 good questions on the board and a whole lot of questions that we couldn't answer with the information given.  I starred the good ones and told them to pick three that they would find the answer to by showing their work and explaining what they did.  I am going to give them some more time tomorrow to work on it, but so far the work looks good!

My second and third classes had a little more trouble coming up with the questions, they couldn't get passed trying to find out when it would be paid off or if it could ever be paid off.  I told them they needed to think about questions we could solve in class with the information given.  We are going to work on it some more tomorrow and they will write their final solutions.  

So now what I am thinking is how to do problems like this in the beginning of lessons not just as an assessment.  I would love to introduce topics this way and have them excited to figure out how to solve them.  I think what holds me back is if I give them problems that they don't know how to solve yet they will get frustrated.  However, I need problems like this to get them hooked and focused!

1 comment:

  1. I think this is a great problem, not just for the beginning, but also for the end! What I really like was that you had them narrow their focus to things that could be solved with the given information. I think if you did that at the beginning, you would get a much different set of questions since they hadn't talked about the scientific notation.

    This is great! Thank you so much for writing about it! I'll keep these things in mind when I'm doing my own "I notice, I wonder"