troydaniels: Plus an idea that just popped in my head as I read your last post. (and an idea that may be good or bad - but not sure since I've only given it a thought for the past minute)
How about: 1 bonus point when your shot shows a 1 2 bonus points when your shot shows a 2 ... and so on for 3-8
Of course once a frog is guessed, the "1" that is shown for that frog NO LONGER gets bonus points.
Even though this may not solve the problem, but it could start to reward the player who makes shots to show more of the board - and not shots to "waste" so they don't give any information to their opponent.
Again, an idea I would have to think about a little more. (maybe even double bonus - 2 points for every "1" your shot shows, etc....)