Showing posts with label probability. Show all posts
Showing posts with label probability. Show all posts

Friday, June 10, 2011

Mandarins in maths class

Think you're perhaps giving too many chocolate rewards to your class? I decided to switch to a healthier treat : mandarins. They are on special right now in Sydney - so even better for the underpaid teacher. Much to my surprise, students really take to them. I put a big pile on my desk to build interest and then at the right time, it's Mandarins for Maths!

A special mathematical treat. Read more about mandarins at
http://www.sevenfields.com.au/products/citrus/mandarins.aspx

My Year 8 class is studying probability, so I posed the question: "What is the probability a segment in a mandarin has seeds in it?"  Someone asks: "Do you mean we get to eat them?" I smile : "Of course!" I asked the students to draw a table in their exercise book to record the total number of segments, and the number of segments with seeds. We agreed how to count them, and then I handed out the mandarins - one for every two students, and we are off doing mandarin maths. Five minutes later I asked a student to each visit each pair, collect their data and then aggregate it. We worked out the probability together.

So what's so great about mandarins for maths?

  • Mandarins are healthy - maths is good for you
  • Mandarins are yummy - maths should be yummy
  • We get to share - just like a good maths activity - it's better in pairs! (Feel the love)
  • Mandarins are clean and easy to handle
  • Low risk of allergies (still worth checking though)
  • There are so many maths questions you can ask about mandarins. 
The disadvantages? Mandarin peel and seeds everywhere. Easily solved - ask a student to walk around the class with a bin to collect the scraps.

There is of course a place for chocolate in every maths class ( I have been building a stash of Toblerone bars ready for volume of prisms work), but definitely think about the healthier options - mandarins were an absolute winner with this class.

And the answer to the question? We ate 194 segments, and 46 of them had seeds - so we worked out a probability of 0.24.