The idea of a person coming back as a ghost to find out who killed her has been done before, but is a nice enough idea.
The plot, the red herrings, the eventual motive and uncovering are quite well put together and the acting by all the teenagers was not at all bad.
My problem is with the adults. Their performances are so ridiculous, that they have careered into caricature, so much so that it threatens to drag the rest of the movie into dis-belief.
I'm guessing that the performances were directed this way for humour, to me it wasn't necessary and there was enough light hearted moments throughout the rest of the movie to keep people happy.
Not a bad movie though and worth watching for the teen age group.