Here is a collection of six Franny K. Stein Mad Scientist books appropriate for ages 7-10.  There is one hardcover and the rest are paperbacks.  Here is what you get:

• Fantastic Voyage


• Attack of the 50-Ft. Cupid


• Lunch Walks Among Us


• The Invisible Fran


• The Fran That Time Forgot


• The Fran With Four Brains (hardcover)