A network + cert kit would be pretty beneficial if you ask me.
This is the book I used while in an Information Technology class during high school. I haven't taken the Network + exam yet, but I have taken a "practice" exam that simulated what the actual exam would have been like. Had I focused a little more I'm sure I would have passed.
And since you've done a test and got to look at some networking questions, you should know at least some of the stuff to look at.