Yes, ma'am. There are a lot of times classes that are offered at their own police academy, basically road officers responding to homicide scenes.
It is not only training, a lot of times kind of fall backs on common sense. If there is something, be it a shell casing or piece of clothing that you know is part of evidence or evidentiary value, most anyone will typically mark that, be it with a piece of crime scene tape or traffic cones, they will set stuff near items just so one, it is marked and they know where it is at. Two, so someone doesn't accidently step on it or kick it or move it.