Bats at the Beach was read on NPR's "Weekend Edition Saturday" by Daniel Pinkwater, after which the book enjoyed a great deal of success, at one point ranking at No. 2 on Amazon.com, and leaving Houghton Mifflin to keep up with the sudden demand. It also landed a spot on Publishers Weekly's children's picture book bestseller list and was awarded an Oppenheim Toy Portfolio Gold Award. The story follows a group of bats, young and old, and their comical variations on such activities as sailing, surfing, putting on lotion, and roasting marsmallows. Matt Berman of Common Sense Media praised the book’s “simple and joyous concept” and noted the characters' gently rounded features. Lies stated that he tries to keep the design of his animal characters as naturalistic as possible despite their often human-like behavior. Lies got the idea from his daughter, who described a pattern of frost on the window as "a bat, with sea foam"; as Lies developed the idea, the verses came to him in a sudden inspiration. The acylic paintings use a lot of blues and browns and are often bathed in moonlight though no moon is ever seen. The sequel, Bats at the Library, made it onto Time.com's Top 10 Children's Books of 2008 list, and the ABA announced that the book had been named Best New Picture Book in the 2009 Indies Choice Book Awards.

Judith Constantinides, in a review for School Library Journal, said his acrylic paintings for Donna M. Bateman’s Deep in the Swamp are reminiscent of an Audubon painting. (The book also won a 2008 Southern Independent Booksellers Association Award.) Constantinides, in an earlier review for School Library Journal, praised Lies’ Hamlet and the Magnificent Sandcastle (which he wrote and illustrated) for its watercolor illustrations and the humorous details. The book is about an optimistic (“despite his namesake”, as Constantinides notes) pig named Hamlet and his “pessimistic” porcupine friend Quince as they struggle to defend a giant sandcastle against the waves. Popcorn! by Elaine Landau was nominated for the 2006 Rhode Island Children's Book Award. and was also included in the Children's Agriculture Book series of Wisconsin Agriculture in the Classroom, which tries to select books that "hat accurately portray modern agriculture".