Sam, Joe, and Fred finish their school project on ancient Egypt without using their magical time travel book, but when Joe's sister Anna plays with it and travels to the land of pyramids, they must follow her back in time to bring her back to 1996.
A transmission received from outer space in a combination of different Earth languages tells of an alien schoolboy's fantastic excuse for being late to school again.
After the frog turns into a prince, he and the Princess do not live happily ever after and the Prince decides to look for a witch to help him remedy the situation.
Thanks to their magical book, Fred, Sam, and Joe inadvertently travel through time to 1877 New York City, where they and their granddaughters, who have also come from the future, help them find a way back to their own time.
While on a field trip to New York's Museum of Natural History, Joe, Sam, and Fred travel one hundred years into the future, where they encounter robots, anti-gravity disks, and their own grandchildren.