SOLVED. Recent YA book, kind of like Percy Jackson. Boy goes on field trip with class and crosses a wall only people with special powers can cross. [s]

[AquaMoon]

Boy, who is kind of a misfit, goes on a field trip to the country with his class and comes across a wall. He scales it and finds himself in a magical world. Turns out he has powers and only those with powers can make it to the other side of the wall. I believe the title had something to do with Mermaids. I started reading this about a year ago, but had to return it to the library before I finished it. I'd like to finish it...IF I can find it.

[Grace]

Hi Alissa,
Could you check with your library to see your borrowing history?

[AquaMoon]

Hannah wrote: "In Other Lands by Sarah Rees Brennan?"

Hannah! This is it! Thank you :)