The content of your LPN entrance exam should be based on your general ed type stuff. Math, reading comprehension, ability to write (probably a very short essay on a random topic), grammar
, punctuation, etc. I don't think it's stuff you can really go and 'cram' for.
Some schools give the NLN exam and I've never had to take that, but have heard it's general knowledge content as well. They know you're not a nurse yet!
I just finished LVN school and mine was given by the school and created by the school so I can only speak from experience. It's not something to really sweat. I'm sure you'll do just fine!
Best of luck,