For Norwegian B: If you already have a moderate vocabulary, seek out online resources. When it comes to learning a language, as long as you aren't at the very beginning of learning it, and you have most grammatical and pronunciation basics down, it's usually fairly easy to pick up vocabulary on your own. Some methods for doing this:
Use Quizlet to find and use other people's vocabulary lists and use those
Read children's books or books geared towards to language-learners of Norwegian
Some teachers upload their content online for their students' reference purposes and whatnot - see if you can find any teacher's websites where they've uploaded their course content
My personal favourite way to pick up more varied vocabulary is to read through a passage of text, make a list of all the words I don't know in the language, use a dictionary to find out what those words are, then study that list of vocabulary.
For Biology: I tend to just take tons and tons of notes, and then make note-cards to get information down. I don't know about you, but writing things down tends to help me. If you get a study guide, make a photocopy of it or something, complete it once, and after some studying, complete it again, just to make sure you're retaining the information and can call to it when prompted on a test. Also, BioNinja is an absolute dream. Some of my 2nd year peers use it as their sole study source and score highly in class.
For Math: Just do problems every single day. Every. Single. Day. Math is something that needs to be drilled and done regularly. The advice I gave you on photocopying your bio study guides is even better advice for math. If you get a study guide, photocopy it, do it 2 or 3 times over.