Day 7: Christmas Maths Worksheets Part 2

It was weird that when I searched recently for Christmas maths worksheets that this one didn't come up in the first couple of pages. I even tried searching for the specific topics I knew the sheets were on, but no result. I had to go to my hard-copy Mathsmas folder and find the URL there. They are from Maths-Worksheets who have a whole section on Christmas worksheets. How did this not come up??

Sheets include loads of topics, mainly worded problems based around a Christmas theme. They range from basic operations up to some difficult data, probability and measurement problems.

Favourites of mine include the ones about wrapping paper and ribbon required for wrapping different presents (perimeter and surface area), the temperature in different areas around Santa's workshop (negative numbers), and how likely you are to pick a present of a certain colour out of a stocking (probability).

Probability Games and Worksheets

My year 9s have been doing a topic on Probability. I like to start with some simple fun activities, including playing Deal or No Deal online. This group got so into it and wanted to play all the time, so I made a worksheet to justify us doing so!

My method of eliminating composite numbers first seems quite successful. Deal!

You can find my Deal or No Deal Worksheet at a lovely resource site called MathsLinks, in the Maths Faculty section. You have to login but you can do so through google or facebook or various other things as well as registering with the site individually. It is a valuable repository of resources and ideas provided by Maths teachers.

The other game I love is Higher or Lower at subtangent.com, so I made a worksheet for that to, which is also uploaded to MathsFaculty. The Higher or Lower Worksheet is simple theoretical probability.

With both of these, I like to run through the game a few times, discuss the theoretical probabilities on the board as we go, then follow up with the worksheet, and maybe a promise that if there's time the student who does the best work can be the next contestant.

(Oh and it was a good deal, I only had $2000 in my suitcase)

Capture-Recapture

Actually my colleague Michael's lesson, but he generously allowed me to blog about it, because I thought it was a great and cute idea. I'm retelling it as closely as I can to the way he told it.

"There's plenty of fish in the ocean. But how many?"

"Here's the ocean. You can tell because it has fish in it. And a sea monster. Who is willing to brave the sea monster and go fishing?"

"You got a fish!" A yellow counter is removed. "What kind of fish is it? It must be a goldfish!" More yellow counters are removed. "They're all goldfish!".

"We've removed 20 fish. Now we are going to tag them." Twenty removed yellow counters are replaced with red counters. And returned to the ocean.

The ocean is shaken around for a bit.

Now the fish are recaptured in different sized samples and the results of tagged-untagged recorded. These are used to estimate the number of fish in the total population (a number unknown even to the teacher).

Then, since our ocean is only a small ocean, the real number can be found and compared to these values, and we can start asking the interesting questions. Which was the closest estimate? How did sample size in the recapture change the estimates? How accurate is capture-recapture?

I'm pretty sure now that all spare cardboard boxes should become monsters of some kind.