Do I have enough wrapping paper?

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I have to wrap this box.        

In this problem based activity students first guess and then try to calculate whether they will have enough paper to wrap this present without taping pieces of wrapping paper together.

wrapping paper

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...with this wrapping paper ...

Shipping Crunch

Now that the shopping season has begun, it's time to get the packages to your homes.  Two big companies take care of a lot of that shipping.  How do they manage that?

The mechanisms for these two shipping giants are huge. Did you ever wonder how they pull it off?  To me they both seem to do a great job.  Is that consistently true.  What are the numbers like?

(Teachers might start this lesson by asking kids to predict what percent of holiday gifts are delivered on time and what percent are not?)

Leaves are pretty but …

Brian has spent too much time thinking about his leaf raking. He's worried about doing the job alone and about how long the job would take with different numbers of rakers.

In this activity students see the inverse relationship between number of workers and time to complete the whole job. They graph hyperbolas and consider how long the extreme condition of zero people raking might take to complete the job.  

Egad! It’s already time for Hanukkah

Sunday evening, December 2nd, is the first night of Hanukkah this year. I think it was much later in December last year. Why isn't it always on the same date? Students look at the Hebrew calendar and appreciate the incredible mathematics involved in creating a calendar that aligns both the moon's revolution about the Earth and the Earth's revolution about the Sun.