An STL implementation has a few things going in its favor:
STL implementations use best-of-breed algorithms.
The designers of STL implementations are, more than likely, domain experts.
Those domain experts were entirely focused on the mission of providing a flexible, powerful, and efficient library. This was their primary task.
But then again. (only) You know your own usage scenario, data types and platform. That knowledge can probably offer some profound short cuts and optimizations.
I don't know about the rest of the world. But in Sweden, the modern view of a teachers roll is one focused on pedagogics. And the mindset of a good pedagogue basically boils down to "It is what is. Deal with it."
"The kids are lazy" is never a valid reason for low performance. A proper pedagogue takes 100% responsibility for the situation in the classroom. It is your job to motivate them.