As a teacher, I believe in triage.  At the top, there are students who pick up the material with minimal effort.  At the bottom, there are no-hopers who cannot seem to learn.  In the middle are students where you think that some effort can make a difference.
In college, taking statistics or economics, I was one of the students who picked it up with minimal effort.  On the other hand, as a folk dancer, I am a middle student.  I am better than the no-hopers who never go beyond beginners’ sessions.  But I am not as good as the dancers who can pick up a new dance right away.
Based on my experience with folk dancing, here is my advice to middle students.
1.  YouTube is your friend!  I encounter many dances that I wish I knew.  Before YouTube, I had to muddle through and make mistakes, or give up altogether.  Now I have been able to add some of these dances to my repertoire.  Similarly, for statistics and economics, just about any concept you would want to learn has a YouTube video.
2.  Give yourself more practice than you get from the teacher.  Sometimes, a dance session leader will teach a dance for a couple of weeks, then forget about it for a couple months, then put it on again and expect students to remember it.  This will leave me totally frustrated if I have been passive.  But I can do something about it by practicing the dance on my own, in order to make up for the inadequate practice at the session.  As a teacher, after I finish a unit, I often stop giving practice questions on that topic.  When I do this, if students want to remember the concepts, they will have to practice on their own.
3.  Identify your weak spots and work on them.  You can keep doing a dance wrong week after week.  Instead, make a mental note of the parts that give you trouble, then later go to YouTube until you have them ironed out.  Similarly, if you got a problem wrong, come back to it and do it correctly several times.
4.  When you watch someone doing something, articulate what they are doing.  If you trying to learn a dance by following, try to say to yourself the steps that the person is doing.  Saying “right, left, cha-cha-cha” helps you learn more thoroughly than if you simply follow along.  Similarly, if a teacher is doing an exercise in statistics or economics, try to articulate the steps that the teacher is doing.  (“Deciding whether this is a shift in demand or a shift in supply” or “using the binomial distribution” or somesuch.)
5.  Make the subject seem really important to you.  Think of someone you have had a crush on, and pretend that the way to get them to notice you is to become good at the subject.