Design your course with a movie theme. Each hole could be based on scenes or characteristics of particular movies. An "Apocalypse Now" hole would consist of a jungle setting complete with a camouflaged hole. For "The Wizard of Oz" construct a yellow brick road leading to a hole behind a curtain. "Star Wars" would require hitting the ball into a Death Star.
You could also design a golf course based on your favorite city. For a New York theme, you could require that the golf ball enter the "city" by hitting it through the Lincoln Tunnel. A miniature East River could make a challenging water hazard, and a shot through or around a replica of the Empire State Building could be necessary to reach a hole on a Manhattan street.
Convert a vacant building into an indoor miniature golf course. Indoor courses can be made from as small a space as 3,000 square feet. You can check your area for empty buildings like convenience stores, furniture stores or gas stations. You could even check the local mall for any vacant storefronts that are available for rent or lease.
Set up a miniature golf course in your basement for the kids. Plastic miniature golf courses are available for purchase and can easily be assembled and disassembled (see Resources). The individual pieces can be reconfigured to change the course design, which can help keep the kids interested. Or make one with what you have on hand.
Consider setting up a homemade course in the backyard for a special event such as a kids' birthday party. Common household items like cat litter can be used to create sand traps, and a backyard pool can serve as a water hazard. Use patio furniture to create obstacles, and turn coffee cups on their side to create holes.