Qwerty Stevens, Back in Time

by Dan Gutman

Published 1 December 2002

The Edison Mystery

by Dan Gutman

Published 1 July 2001
Thirteen-year-old Robert "Qwerty" Stevens uses the time machine he finds in his back yard to visit Thomas Edison's workshop in 1879, and there helps develop the electric light bulb, but then needs his sister's help to return to his own time.