For a week in March, 35 young students carried  two-by-one foot pieces of lawn around Chicago with them.

They took care of their sod chunks, and brought them to classes and into restaurants.

The students, chosen by their art teachers, photographed themselves  as they nurtured their tiny lawns for a week. One girl snapped an image of herself sunbathing alongside her strip of sod. Another put the piece of lawn on top of the grill, instead of the other way around.

No, this wasn't an unusual homework assignment. The photos and the students' personal observations were part of a project by Lizabeth Eva Rossof, an artist and Chicago native.

Rossof's array of photos and student comments make up one of the displays at the Peggy Notebaert Nature Museum's newest exhibit, Lawn Nation: Art and Science of the American Lawn. It opens Friday.

According to the museum, lawns are the most common landscape in America. The country has 60 million of them.

Shane DuBow, strategic projects manager at the museum, says anything that covers so much of the land is worth a closer look.

Through a series of photos, audio stories, documentary films and interactive exhibits, Lawn Nation examines the history of lawns and their cultural impact. It also explores alternatives to sod.

"Lawn is a choice. It's not a biological imperative," DuBow says.

Choose Your Own Adventure: The Lawn Conundrum, an interactive computer game, lets visitors examine that choice.

The game puts visitors in control of their own digital lawn. Players decide what to plant, and how often they want to water or mow their lawn, and see the consequences for each decision.

Lisa Loeb, one of the game designers, says conventional wisdom dictates how lawns are kept: "Of course, I can't have dandelions, and of course, I can't let it go brown. [But] in fact you really can."

The exhibit also offers tips for environment-friendly lawn care. The museum's outside space plays host to a display of alternatives to turf grass yards.

Visitors can view a lawn made of edible plants, and another created with medicinal herbs.

The exhibit also celebrates the lawn by offering space for traditional backyard games. 

 "Who doesn't want to play croquet?" Dubow says.