Danger Down the Nile by James Patterson and Chris Grabenstein
Meet the Kidds, the four children of Tom Kidd, a world famous treasure hunter and oceanographer. In book two of four in the Treasure Hunters series,the four kids, Storm, Tom, Bickford and Rebecca are on a submarine looking for their mom and dad. Mom is being held captive and dad is missing. The kids do what they do best. They look in Africa, Egypt, and China to find what and who they need.
While they are homeschooled in math, science, languages, music lessons, martial arts and acting lessons, these worldly kids also have special talents. Storm memorizes anything that she sees. Tommy is open minded and optimistic. Bickford, "Bick", and Rebecca, "Beck", the twins, are brave as lions when Guy Dubonnet Merck, their arch villain is around. You should see how they use snack cakes as weapons! Twinkies to the rescue!
Readers of the Geronimo Stilton series and the Treehouse series by Andy Griffiths will find that the fast paced, plot driven adventure story will ring funny.