"The Kidd children--including twelve-year-old twins Rebecca and Bickford--follow mysterious clues that take them from China to Germany, in the hopes of finding their missing father and the treasure that will finally free their kidnapped mother"--
"Robots on strike! Sammy's underappreciated mechanical helpers cause chaos in the house! It's up to Sammy and his disabled sister Maddie to keep the peace until his inventor mom reveals her secret project ... and why it was worth the wait"--
When they uncover a conspiracy against America and its fundamental freedoms, the Kidd children, accompanied by their great uncle, crisscross the country in a race to prove that a newly-discovered copy of the Bill of Rights is a forgery.
"Fifth grader Sammy Hayes-Rodriguez has to find a solution when his robot 'brother' has repeated malfunctions at school and a newer model robot steps in as competition--and his mother's job is in jeopardy as a result"--