11 books • 4 series
Book #4: The Classical Student Planner
Book #1: The Case of the Claymore Diamond
Book #2: The Maths Inspectors
Book #3: The Math Inspectors 3
Book #4: The Math Inspectors 4
Book #5: The Math Inspectors 5
Book #4: My Investigation Journal
Book #2: Write-Your-Own Comic Book