A great resource for finding sample games is Board Game Geek. Interested in a zombie game? Search "zombies" and track down games with that theme. Most games include screen images of the board, game pieces, cards, etc., plus rules and general descriptions. I used it to get ideas for a football-based grid game I played around with (see here and here) and I was amazed by how many football games there have been and how many different forms they have taken.
Remember: grid games can take many forms. Don't be confined by the games you know -- try to learn about more games and ideas to expand your horizons.
Or just try to do something innovative by starting with a question, such as: "What would a grid game based on a hexagonal grid be like?" It might get you to start thinking about bees or space ships. And then you begin to get ideas....
Among the more interesting grid games developed in this class have been:
- Zombie Mansion
One player commands the Zombies and tries to keep the humans from escaping a mansion house. As humans get bitten by the zombies, they join the zombie team and give the zombies more turns. Surprisingly, the zombies usually lose. Little zombie pieces, available for sale online, make this really fun.
- Jungle Escape
Be the first player to escape the jungle by making your way down a mountain to civilization. Manage your resources and trade with the natives. A race game with strategy.
- Pizza Mania
Shoot your game piece onto the wavy-cheese grid board to select a topping card. You need to win four topping cards to win the game.