Blogs » Janey Lacks Blog » Birthday Probability Problem


What? Actually, that is the title of one of the hundreds of "YouTube-styled" short courses designed and delivered by Sal Khan on his highly-acclaimed Khan Academy site (

Please go there! It's brilliant. It's seriously breathtaking!

With a keen understanding of all things mathematical (and so much more!), Sal Khan has built a staggering array of mini-courses, each delivered with easy-going clarity in 10-minute YouTube segments.

The first module I explored was about averages. It was my goal to gauge the accuracy of the material. From there, I moved to subjects I didn't know to see if I learned. My brief "back-to-school journey" ended with a huge wish that this had been available to me when I was a student. Not only was the material clear and engaging, I could go back over it as many times as I wanted and whenever I wanted.

An intellectual magician, Mr. Khan has taken complex issues, found their essence and transformed puzzles into engaging and easy-to-absorb learning moments. These videos give voice to a brilliant and focused mind amazingly available to the world now through the power of modern technology.

Originally created for his seventh-grade cousin, these beautifully-casual but intellectually-rigorous YouTube lessons are a gift to all of us.