This is gonna be short and simple. If you are taking engineering, these channels are a MUST.
* Calculus
PatrickJMT
This guy is the god of mathematics tutoring. He carried me through calculus.
* Statics, Dynamics, Stress
StructureFree
This channel has a vast amount of resources. STRUCTUREFREE! They are very clear and funny.
DrYWang
Not as fun to watch as StructureFree, but great content.
* Prerequisite Knowledge
Khan Academy
You all probably know Khan Academy. Has all the basic stuff, but I didn't find it as useful for more advanced topics. Very good for fundamental review.