About the Practice Final Exams: 
Each year, I adjust slightly the topics covered in 326, so there are a couple 
of questions in the old finals that I would not ask this time: 

- Spr16 Problem 5: This semester, I did not derivate the wave equation
  for the transverse oscillations of a continuous string under tension. 
  The solutions are a series of "harmonics" = sinusoidal solutions that
  are anchored to zero at the fixed ends of the string.  It is really
  not a hard problem, but I would not ask it this time since we didn't 
  talk about it.

- Spr 15 Problem 1: I did a review of 1D damped/driven oscillators in 
  spring 2015, then realized it was a waste of time since it is thoroughly 
  covered in your differential equations courses.  Problem 1 is a simple
  problem - it is very good pratice! - but I would not ask a purely 1D
  oscillator question this year.