I am totally against vet students doing any kind of procedures on my personal animals or of  those that I'm fostering.  If they need to practice, the best place is at a low cost spay/neuter clinic where feral cats are brought in for the trap/neuter/release program. 

If this is to be considered, there needs to be many regulations put in place.  First and formost..........and owner needs to be told before their animal sees the vet that a student may be doing the exam or procedure and written permission needs to be given.  I don't mind a student observing my vet when he sees my pets, but I'm paying for a vet to see them and don't want an inexperienced student doing any procedures on my animals.