Cory in the House is an adventure game that requires the player to play as Cory Baxter, a teenager who lives with his father Victor Baxter after Victor gets accepted as head chef at The White House. The basic premise for the game is Cory, after winning a toy contest, starts an endeavor to sell bobbleheads depicting the President of the United States to the citizens of Washington, D.C.. The bobbleheads however are taken into possession by The Evil Toymaker, who tries to utilize the bobbleheads as a means of hypnotic technology on the population of Washington, D.C. Cory is then tasked with retrieving the bobbleheads to stop the hypnosis plan.
The gameplay can be described as an adventure stealth game, where the player controls Cory and his friends as they move through locations including halls in The White House, a school, a mall, and streets of Washington, D.C. Tasks involve sneaking past Secret Service agents, examining rooms for specific items, throwing pastries at hypnotized teachers, and talking to non-playable characters. Additional features include mini-games, which involve tapping the Nintendo DS stylus against the touchscreen along with music or simulating connecting electrical circuits.