Hammer into
Definition 1 of 2
Pro Tip 1/3Strong Emphasis
The phrase suggests a forceful and persistent way of teaching. 
Our coach hammered sportsmanship principles into us.
Pro Tip 2/3Emotional Frustration
Sometimes used to express annoyance towards someone's learning process. 
I keep hammering the rules into him, but he forgets!
Pro Tip 3/3Repeated Effort
It implies repeated instruction until the lesson is learned. 
The tutor had to hammer the formulas into the students.