Two summers ago back when I was a lazy and all-around poor student, I took DiffEq at a community college in 5 weeks because I had heard it was easier than during the regular semester. It was easy, but I didn't end up learning anything (mostly my own stupid fault), and now I'm wondering if I should take DiffEq again this spring at my 4-year university? I am a much more serious student now but I can't decide if it would even be beneficial for me to take DiffEq at this point seeing as it's a purely computational course at my school (no proofs) and I like to think I've reached the point where I only take proof-based classes. I'm signed up to take intro to real analysis and intro to abstract algebra next semester and since I don't like taking more than 3 math courses per semester, it has come down to choosing between DiffEq and intro to number theory (all proofs). I realize DiffEq is an important subject (probably far more valuable to math majors than intro to number theory) so I was thinking if I don't take it in the spring I could self-study it this coming summer with the theory. Advice?