The first-year teacher gets plenty of exercise racing up and down the three flights of stairs at the Far Northwest Side school and wheeling giant carts laden with paints, crayons, pencils and scrap paper from classroom to classroom.
"It's very hard," said Rachmaciej, 24, who graduated from Northeastern Illinois University a year ago. "But this is an amazing job. I just feel so lucky."
Dever Elementary — which data from the Chicago Public Schools shows is one of the most overcrowded schools in the city — doesn't have enough space for a dedicated art classroom. Instead, Rachmaciej travels from room to room, teaching students how to draw, paint and sculpt.
"We make it work," Rachmaciej said. "Whatever I need to do so they can learn and create and experiment, that's what I do."
One of Rachmaciej's most popular lessons focused on origami — the traditional Japanese art of paper folding. Inspired by eighth-grade students who were creating paper cranes in an after-school art club, Rachmaciej introduced it to the third- through sixth-grade classes.
"It is really inspiring to watch the students' reactions to what they can do," Rachmaciej said. "Everyone might not be able to draw, but everyone can fold a piece of paper. It is a big result."
Rachmaciej has also taught her students how to make masks, using colors to depict emotions and feelings.
Other classes have studied the work of Andy Warhol, creating self-portraits after learning how to draw the various shapes of people's faces — complete with "football-shaped" eyes.
After drawing a self-portrait, second-grade students in Lauren Simmons' class used their drawing to re-create the famous repeating images of Warhol's work. Then, gleefully cheering Rachmaciej's unveiling of tempera paint and paintbrushes, the students covered their desks with newspapers and got to work turning their black-and-white sketches into surreal pop art.
As they worked, Rachmaciej went from desk to desk, answering questions, giving gentle reminders and making suggestions.
"Your hair is looking a little like a mushroom here," Rachmaciej told one student, prompting gales of laughter.
Rachmaciej urged another to lengthen his portrait's sideburns, ruffling his hair and telling him "you are too cute to look like an old man."
The last 10 minutes of the class were devoted to cleanup, making sure the room was ready to turn back into a classroom from a painting studio at the sound of the bell.
Dever's "ideal capacity" is 630 students, but 844 students were enrolled in the school on the far Northwest Side, with a utilization rate of 134 percent, according to data provided by school system officials.
Illinois Raise Your Hand, a parent-run group, has criticized the school system, saying its calculations underestimate overcrowding.
In February, Dever Principal Rita Ortiz pleaded with officials to ease the overcrowding at Dever, which she said made it difficult to create a calm culture of learning. Despite the school's space challenges, it is rated Level 1, which is the district's highest performance rating.
Ortiz used the extra 30 minutes Mayor Rahm Emanuel ordered to be added to each school day at the beginning of the 2012-13 school year to add art to the school's curriculum for the first time in a decade and hire Rachmaciej.
"It's great to have art back," Ortiz said. "Now pictures line the halls of our school, as they should."
Rachmaciej does her best despite the space crunch, and collaborates with the classroom teachers to make sure her art lessons inform the students' other work, Ortiz said.
"It would be great to have an art room," Ortiz said. "But right now, that just doesn't exist."