"Twists and turns in the plot keep readers guessing until the very end. The story, over-the-top funny, combines Alex Rider’s espionage skills with a huge dose of the sarcasm of Artemis Fowl."
– School Library Journal
"This romp is a great choice for reluctant readers of either gender."
– Booklist
"Spy School will keep young readers engrossed from cover to cover."
– Bookpage
"Many, many kids enter middle school wishing they had a license to kill, but until the CIA comes knocking, this exercise in wishful thinking should keep them mightily entertained."
– The Bulletin of the Center for Children's Books
"A race-to-the-finish thriller."
– Shelf Awareness