I Spy Year Round Challenger: A Book of Picture Riddles

I Spy Ultimate Challenger: A Book of Picture Riddles

I Spy Gold Challenger: A Book of Picture Riddles

I Spy Super Challenger

I Spy Extreme Challenger: A Book of Picture Riddles

I Spy Fun House: A Book of Picture Riddles

I Spy Mystery: A Book of Picture Riddles

I Spy Fantasy: A Book of Picture Riddles

I Spy Treasure Hunt: A Book of Picture Riddles

I Spy School Days: A Book of Picture Riddles

I Spy Spectacular: A Book of Picture Riddles