The Octagon Valley Books in Order

The Octagon Valley books take Melissa de la Cruz into younger middle-grade adventure mode, with more jokes, gadgets, and puzzle-solving than romance or dark fantasy. The setup is pure invitation: an exclusive high-tech institute run by a mysterious genius, a group of unusual kids, and a weekend that quickly becomes much stranger than any school visit should be.

Edwin Edgefield opens the door.

Edwin has the kind of gifts that make ordinary school life difficult, including a near-photographic memory and standout math ability. When he gets into Octagon Valley, he hopes he might finally meet kids who understand him. Instead, he finds a pack of fellow misfits, each with their own odd talents and quirks, and a program filled with bizarre tests, hidden motives, and escalating danger. Escape rooms, zero-gravity chambers, piranha-filled obstacles, and moon-bound missions give the series a cartoonishly fun energy.

What makes the books work is the team dynamic. Edwin may be the entry point, but the real pleasure comes from watching a group of kids who do not naturally fit together learn how to function as one. The series treats their differences as strengths, even when those differences also cause plenty of friction. That makes the books good for readers who like found-family adventure as much as the high-concept setting.

The Octagon Valley world is also built for momentum. Every test suggests a bigger mystery. Every wild challenge hints that the adults know more than they are saying. The tone stays playful, but there is a genuine sense of forward motion that helps the series feel more substantial than a string of random set pieces.

If you want a Melissa de la Cruz series for younger readers that emphasizes curiosity, teamwork, and offbeat adventure, this is the lane. It is less about emotional intensity and more about smart kids, strange missions, and the delight of discovering that being unusual might be exactly what gets the job done.