In my experience (having programmed in over a dozen different computer languages, and learned a smattering of a dozen more), the only way to learn a computer language is to write programs in it. Lots of programs. The first few may be trivial examples -- indeed, they may be copied verbatim out of a textbook -- but you need hands-on experience making programs work before you can consider yourself a competent programmer in a particular language.
So I expect you to design, write, debug, and test a lot of programs. A few of these programs (probably one a week) will be specifically assigned, to be turned in. But for the rest, you're on your own. When I describe a new language feature or a new programming technique in class, your first thoughts should be ``how can I try this? how can I use this to do something nifty?''
Programs are not abstract works of art, they are supposed to run and solve real problems. So if I get a program that doesn't compile, or a program that has little or nothing to do with the problem I assigned, I will give it a zero, no matter how much time you put into it. Don't turn in a program you haven't tested yourself: if you can't be bothered to test it, I can't be bothered to grade it.