It's funny because mine was math so pure that the final was "Imagine a function that does xxxxxxxxxxx. What would happen if A) yyyy? B) zzzz? C) ppp ddd qqq?" No numbers. Fuckin' essay-style with roll-your-own functions and derivation. It was eye-poppingly hardcore. The rate of attrition in that class was such that 15% of the people who started it finished it. I got a 25% on the one assignment he gave all quarter and immediately asked him what I could do to resurrect my grade. he said "relax! You were in the top 20%!" When all of us were heads down and desperate on that final he said "if you take it home and study I will give you an A." Fuckin' A I'll bet I could teach Diff EQ even now and it's been 20 years. That class was goddamn amazing.
Maybe it was my professor - he was basically like "here's a Laplace and this is how you calculate a Wronskian so go do that now okthxbai". He never explained why things were done that way properly, so I had to resort to fucking Khan Academy more than once to understand what was happening.