# The Algebra Toolbox

## My Best Number

73 The Best Number in the World

One of my many goals this year is to increase number awareness and number sense in my students.  This open-ended get-to-know-you assignment was a good start.

First, I showed the students this 1:00 minute video clip from youtube to introduce the idea of the “best” number. (Use caution if you just search for Sheldon Coopers best number on youtube. One version explains Raj’s favorite number 5,318,008 because it spells boobies when you turn a calculator upside down!)  After watching the video, we talked about the types of numbers that Sheldon mentioned (palindrome, prime,  binary, product). I asked what other “types” of numbers they knew. Descriptions such as odd, even, perfect squares, whole numbers, etc were brought up.

I gave each student this  My Best Number recording sheet. (I left room for more “best” numbers so students could add other cool numbers to their recording sheet as they year goes on).  They had to come up with one  Best Number for them and at least 2 reasons why it was the best. The reasons could be mathematical, historical,  or personal to them.  I gave them a couple days to think about it. On Friday of that week, each student shared his/her best number and the reasons behind it. It was a great way to get to know the students. One girl said 10 was her best number because that was how old she was the first time she met her real dad and that’s how many fingers she had to count how much she loves him.  WOW – deep for a high school freshman.  Many students chose their birth date, sports jersey number, etc. but many were very personal.

As we worked through our unit on solving equations, the students substitute their best numbers into equations that had “all real number” solutions to check the validity of the solution really being all reals. They loved that their best number was a solution. As they check their solutions to linear inequalities in the next unit, they will do the same thing.