40 books • 3 series
The Boy Who Walked on Air
The Red Room Riddle (Yearling Book)
Take a Number
The Great Custard Pie Panic
Dr. Merlin's Magic Shop
The Lemonade Trick (Apple Paperbacks)
The Case of the Ticklish Tooth
Steady, Freddie
The Mystery Man
What Makes a Boat Float?
We Lived in the Almont,
Cop's Kid
The Turnabout Trick
What Makes a Plane Fly?
What Makes Light Go on
What Makes a Car Go?