Making your own haunted house right in your backyard isn't as difficult as it sounds, especially if it is designed for children. (Kids are easily impressed, but adults expect wizard gadgetry that costs extra. We'll be sticking to the cheap, easy, kid-friendly tips here).
The most important thing to remember when designing your haunted house is that you are essentially creating a maze. You want as many twists and turns as possible, because each turn represents a new "spooky surprise" for the kids. If your backyard is fenced in, you've got the ideal setup. Simply string clothesline from your house to one fence, and then from that fence to another side of the fence, and then back to the house, so that you end up with a triangle of clothesline. This will form the structure that will hold the "main walls" made out of cloth or sheets, died black.
Next, attach sheets to the clothesline to finish off the "house". Now take your flourescent "glow in the dark" spray paint and get creative on your black fabric walls. Feel free to write scary messages such as "Beware To Those Who Enter Here!" or "Ghosts and Goblins Live Here!", and paint ghost figures on the cloth walls.
Now that the main "house" has been constructed, you need to create the maze within it. Use cardboard boxes or square hay bales to form these temporary walls. Just stack them up, creating narrow "hallways" that twist and turn throughout the "house".
Once the maze is set up, you can get creative in so many ways. Below are a few ideas to help you decorate the place. Keep in mind that you are doing this for kids, so you don't need to be elaborate, and you don't want to scare them too badly. The old tried-and-true tricks of haunted houses past still work just as well today.
Lighting: Of course, you'll want to keep your haunted house lit just enough to make it safe for the kiddies to walk through, but dark enough to make it a little spooky. The best bet is to buy a few plastic jack-o-lanterns and place battery powered candles within each. These will light the way nicely, but will also be safe. Never use real candles or any type of flame.
Sounds: It's a piece of cake to find spooky Halloween soundtracks on cd at any dollar store, so pick up a couple, and have them playing all night long.
>> To show off those glow-in-the-dark paintings you created, you'll need to have a few battery-powered blacklights shining on them. You should be able to find these fairly easily, but if your stores don't carry them, you can always order them online.
>> Fill fishbowls or other see-through bowls with peeled grapes in one, soft, gooey, boiled spaghetti in another, and the icky insides of pumpkins in a third. Create signs that indicate that these bowls are filled with the eyes, brains, and intestines of the ghosts and goblins who once lived here. The sign can indicate that only those who reach in and touch the gooey body parts can continue through. (Of course, don't force kids to touch them. Some will just be too scared to do so.)
>> Hang rubber spiders and bats from strings. You may need to use tree branches above your "house" to hang these. Make them long enough so that they brush the tops of the kids heads as they walk by.
>> Create ghosts with styrofoam balls covered by old sheets. Place these just around a few of the maze corners.
>> Finally, enlist a few people to dress up in spooky costumes (but not TOO scary) and have them scare the kids when the turn corners. These people should keep it fairly tame. Even a slight movement can scare kids, so they shouldn't go overboard when scaring them.
>> Of course, as you start planning, you may think of lots of other ideas so feel free to get imaginative. But if you start with these basics, you're guaranteed to create a fun, spooky haunted house in your backyard for the neighborhood kids to enjoy.