"...My eldest kid is dancing around in my room here because she is so excited that she finally found someone that teaches like this. You're awesome. Thank you."

"I don't know who you are but in my mind you are a savior. My children
really struggle with math, there is an inherited learning disability
in my family. They get it but only after seeing it done multiple
times. Your videos will allow us to help our children get caught up
with their peers. As a parent I have to say, Thank You Thank You
Thank You."

"I've never been very successful with algebra, I know this is pretty
basic, but I have almost no comprehension of mathematics. I was
honestly going to be kicked out of school for being non-productive, I
was ready to be thrown out, but now I get this. Thank you so much..."

"This is my first year in college and until today i was completely lost
in math. Half an hour with your presentations taught me more than
three months of sitting in my professors class. You seriously saved my
grade."

"Thank you so much! Keep up the good work :-D
This is the most useful channel I've come across on youtube ever! Greetings from Denmark!"

"You're the only math tutor that makes sense to me. Most other ones
seem to be speaking some sort of alien math language I cannot
understand, assuming I already know formulas and all that. Thanks for
keeping it simple and easy."

"You are my savior!
I took the SATs during the beginning of the school year and pulled off
a 750 in the math part. THANKS TO YOU!!..."

"You are a living legend as appealing to teaching that is :)"

"hmmh....With you around...Do I really need to go to math class now?"

"Sal, I just wanted to say thank you for all your help. It is
marvellous that someone like yourself gives your time to help better
others. This is especially true as you are helping so many people who
you do not know. If only there were more people like you in the world.
I'm studying physics and I am brushing up on some of my maths skills.
You have been a great help to me, and I'm sure many others like me. I
am just regretful that I have nothing to offer you in way of a thank
you other than this message. If I ever come in to position where I may
be able to help, you will undoubtedly hear from me."

"Thanks for educating all of us who're interested on mathematical
knowledge. Thanks to you I finally see a light at the end of the
tunnel. You're the best. Keep up the good work. If I were an engineer
already, I'd donate money to you for this. I'm not going to forget
Khan's academy."

"...I just wanted to say that out of every internet
learning site I have used yours is by far the best!
The maths [are] just so beautifully explained. Thank you so much; now I
really think I will pass my maths exams~!"

"...Your videos have become very popular in my school, and my
grades have sky-rocketed ever since I became accustomed to your
methods of teaching..."

"...Before stumbling across your video's i had no idea how to relate with
math problems [math is my extreme weak point] but after watching some of your video's, I can
do math without a problem..."

"Thanks so much for your videos, there are immensely helpful. I have
got my entire AP Calculus class watching your videos. :)"

"I am a high school Math/Physics Teacher working in Toronto Ontario. I
have been referring students to your videos for the past year and have
referenced many of them on my website. Those that have used it find it
very useful, and have commented that you explain content better than I
do..."

"I've been re-teaching myself physics with your videos, and I'd like
you to know that you are miles better at keeping my attention than any
physics or mathematics professor I had during my university work (and
I say that while I'm working on my third degree). I only hope Youtube is still around when I have children so I can use
these videos for them as well."