Learning : School
1) Cramming (Memorization). Just memorize the words, stories, methods, algorithms, formulae. That kind of memorization is the activity that is being measured at school exams, where a "challenge-response" style of "authentication to the certificate called mark" is performed.
2) Understanding. Understanding is the kind of activity, where in addition to cramming the learner looks at alternatives and tries to find an answer to the questions, why did the authors of the cramm-able solution chose the kind of solution that they did in stead of using a different kind of solution and how is the crammable solution related to other, previously crammed or understood solutions.
3) Deciphering. As people think differently and Understand and Memorize things by translating the new "words" to series of "previously crammed or understood words", proper teaching includes multiple, different, explanations to a single, deliverable, "word", "concept". As teaching staff is not that thorough or even leave mistakes in to their explanations, students and pupils have to figure out, what the new material is about, what is the thing that they need to memorize to pass the exam.
Activities at School
School is about Cramming, not Understanding. Understanding is a sin in the year 2013 academic facilities, but luckily it is not forbidden either. It's just that the exams, certificates, are for Cramming, not Understanding. Trying to Understand things can take up so much time that not enough time is left for Cramming.
A Hypotheses, how to get Through a University
Look up the outline of the course from the University home page and the home pages of the lecturers, who conduct that course in the given university.
Learn it all from the materials that are available at the home page and other sources to the point that You are capable of answering all the test questions and exam preparation questions that are available at the home page. There is no reason to be overwhelmed by the extent of the material. Serious learning of a course does take a week or two, straight, at least 8h a day, to get through the material.
Often the most advanced topics are not covered well in online material and have to be sought from old-fashioned paper books. Computer Science material tends to be available in electronic form, but pure mathematicians live almost entirely in the world of old-fashioned paper books.
A probabilistic hint: The most popular western universities seem to offer really good entry level online materials, but graduate level courses seems to be missing from the online world of the most popular western universities. Germans seems to offer really nice math related texts, but those are in German.
Register Yourself to the course, which involves paying the course fee and some exact bureaucracy with deadlines, e.g. all fees must be paid before the courses start, etc. Attend all lectures rigorously to rehearse the previously learned material and find out the context and words and style, what the given lecturer expects You to obtain. There will likely be many side-topics, nuances, that might be even irrelevant to the topic, but are pivotal for passing the tests and exams (a cliché: You have to be in the lecture, where the lecturer tells the short anecdote or a joke that will be in the exam). The lectures and seminars are not a place for serious learning, but an intellectually entertaining social event, where You just have to attend and observe, rehearse the previously learned things and find out the nuances and topics that You did not know to learn ahead and all of that without popcorns, because the crunching of pop-corns or nuts would probably disturb other attendees. (As of 2014 in Tallinn University of Technology it's OK to take a cup of coffee with You.)
The topics that You did not know to learn ahead have to be learned rigorously outside of the lecture, probably at weekends, but a good thing abut being enrolled in to the course is that the lecturers can actually be consulted with, asked to explain some things and sometimes they even do explain things without telling that the answer to Your topic will be in lecture X or repeating the same, not understandable, explanation that they gave in a lecture, where you attended and already heard the not understandable explanation.
Submit all homework at least one week before deadline. There might be issues that You forgot to do some part of it or the homework submission software left You homework to be a draft in stead of submitted solution, etc. If You get it all submitted at least by the deadline, then there's at least some sort of a chance that You might et at least 50% of the points and pass the course. Marks are not always given by Your knowledge bout the course material, but for less relevant things like deadlines, text format, following the style of the lecturer, etc.