23 books • 7 series
Sink vs. Float (Science Showdowns)
Magnets Attract vs. Magnets Repel (Science Showdowns)
Renewable Energy vs. Nonrenewable Energy (Science Showdowns)
Push vs. Pull (Science Showdowns)
Influential People Pack C of 2 (Influential People)
Influential People Pack B of 4 (Influential People)
Poison Dart Frogs (Unique Animal Adaptations)
Area 51 Alien and UFO Mysteries (Aliens)
Dirt Bikes (Start Your Engines!)
Unique Animal Adaptations (Unique Animal Adaptations)
Aliens (Aliens)
Area 51 (Aliens)
Construction Vehicles: Bulldozers
Start Your Engines!: Dirt Bikes
Construction Vehicles: Front-End Loaders
Construction Vehicles: Cranes
Construction Vehicles: Excavators
Chadwick Boseman (Influential People)
Excavators (Construction Vehicles (Pop))
Front-End Loaders (Construction Vehicles (Pop))
Bulldozers (Construction Vehicles (Pop))
Cranes (Construction Vehicles (Pop))