David and his family use his grandfather's time travel machine to travel to 1853 Ohio, where they assist runaway slaves on their journey north on the Underground Railroad.
David travels back in time to 1906 San Francisco to try to save the lives of Antonio Giovanni and his family who were victims of the devastating earthquake.
David and his family travel back in time to San Antonio, Texas in 1836 and meet brave defenders of the Alamo such as Davy Crockett.
The Smithers family find Grandpa's old time machine and decide to travel back to 1880 for their summer vacation. David and Jenny learn a lot about their heritage and history on their incredible trip.
David and his family use his grandfather's time travel machine to go back in time to the Chicago where David is teaching four boys to speak English as he experiences the Chicago World's Fair. .
David and his family meet William Henry Lewis, an African American football hero who travels to the future with them when he's injured.
David and his family travel back in time to California in 1849 to experience the ups and downs of prospecting for gold.