Cost: $34.99 kids, free for kids two and under

What to expect: There's trick-or-treating during the day, but at night, Six Flags Great America turns into a land of ghosts and ghouls, with kids' activities (including a Halloween-themed Wiggles show!), two haunted houses, a parade of ghouls, a human freak show and much, much more. Check the website for the full schedule of activities.

Additional info: Note: no costumes are allowed at night.