Anne Kowalski, a 21-year-old DePaul student, is sticking her colored pencils in the microwave.

Kowalski is a coloring book connoisseur.  Endless pages of tiny, colorful details are tacked all over her bedroom wall. There are paisley prints. There is a hypnotizing array of cool blues and soft neutrals. There are even “Adventure Time” characters. She’ll go as far as sealing a finished page with Mod Podge to make them look complete. Colored pencils are her preferred tools, and when the tip touches the page, she lets her mind wander and hands run freely. For Kowalski, coloring is how she manages stress.

“When you microwave for three seconds, it keeps them from cracking when you sharpen them or press too hard,” Kowalski said as she demonstrated with a black pencil. Kowalski said that when her life gets a little crazy, so do the colors on the page.

“If I’m in a bad mood and need to be doing homework, I don’t really have time to think about all of my feelings,” she said.  So she turns to her worn cardboard box that bursts at the seams with a variety of different coloring books.

According to the American Art Therapy Association (AATA), adults may use coloring as a method for anything from exploring their feelings to managing addictions.

“Art therapy helps people resolve conflicts, improve interpersonal skills, manage problematic behaviors, reduce negative stress, and achieve personal insight,” according to AATA’s website. “Art therapy also provides an opportunity to enjoy the life-affirming pleasures of art making.”

Recreational coloring books have been around since the 1880s, but over the summer, a new genre for adults seemed to emerge.  They’re out on display in bookstores in their own section, typically labeled with something similar to “adult coloring.”  The pages in these books, intended for adults, are full of intricate designs and loose instructions to assure users walk away fulfilled and relaxed.

“I’ve been doing this forever.  When I didn’t have ‘adult’ coloring books, I just used kids’ ones,” Kowalski said. “(Adult books) probably existed, but until now, they were a lot harder to find.”

Jamie Yates, an employee of a Barnes & Noble in Lincoln Park, said he could attest to that. He witnessed the extreme rise in demand for adult coloring books about six months ago.

“When we first got this one in, we couldn’t even keep it in stock, ” Yates said while holding a thick coloring book titled “Secret Garden” in a dainty gold font.

The book advertised itself by calling it an “inky treasure hunt,” suggesting that all 96 of its black and white pages followed a search-and-find theme.

Each page, whether designed as a maze or floral pattern, enables its owner to become the illustrator.  Some pages even featured open-ended instructions, such as “Draw a swarm of bees,” or “tangles of vines and daisy chains.”

“Secret Garden” was published in 2013 and now rests, in stock, among Barnes & Noble’s selection of adult coloring books. The books were compiled of intricate outlines for any adult’s interest, ranging from Mehndi designs to ocean reefs, indie rock posters to adult humor.

Though Kowalski loves coloring to relieve her stress, college students may not be the only ones looking to keep their creative consciousness active.

“There’s no single demographic of those who come to purchase these,” Yates said.    

Mary Jane Rattner, a mother of two college students, also uses coloring books to unwind because she said “it’s a process.”

“A friend of mine sent it to me.  She was posting it on Facebook, I commented that it was so cool, and the next thing I know, she sends me one,” Rattner said.

Rattner’s book is full of what she called “stress-relieving patterns.”  Once she was hooked on coloring herself, she then furthered the trend by giving a coloring book of inspirational quotes to another friend.

“All the lines are already there,” she said.  “It’s like architecture versus interior design.   You’re not creating the space, but you get to fill it.”