A DJ mixing station in the sleepover room. Secret passageways inspired by "Harry Potter." A fully tricked-out videogame arcade. You've entered the teen wing of the house.

As parents look for creative ways to keep older kids hanging out at home, some are turning to an unexpected source: architects and designers. The result is a new category of spaces now showing up in family homes: teen lounges, hangout areas, sleepover spaces and "offices" for doing homework.

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