Bill Weber

1. Cộng đồng
2. Positive Stories and Testimonials
3. Thank you so much Khan Academy!

I agree !!  Thank you !!  I am re-studying math from arithmetic through Calculus to prove to myself that the F and the D that I received in mandatory college freshman Calculus were the result of 13...

1. Cộng đồng
2. Positive Stories and Testimonials
3. Sal, an inspiration

I also love Sal's voice and his gentle, patient and non-judgmental way of explaining.  Unlike some of the teachers that I had in school, he has never once yelled at me, laughed at me or mocked me i...