[8] Athenian is a founding member of Round Square, an international organization of schools whose philosophy is influenced[9] by the German educator Kurt Hahn.

He found 80+ acres of land in what was then rural Contra Costa county, a portion of what was then the Blackhawk Ranch, bordering on Mount Diablo State Park.

Athenian's neighbor, Blackhawk Ranch, was sold to land developer Ken Behring, and by 1979 2,500 upscale homes were built.

In 1979, there was sufficient interest in the surrounding community for Athenian to open a day-school-only middle school, serving students in grades 6–8.

The full list of sports offered includes wrestling, soccer, volleyball, ultimate frisbee, tennis, dance, golf, swimming, track & field, cross country, club sailing, basketball, baseball, badminton, women's lacrosse and a variety of other non-team athletics, including hiking, fencing, yoga, outdoor adventure, and weight training.

[13] While Athenian's founder, Dyke Brown, was influenced by Kurt Hahn, a wilderness expedition was not originally required in the curriculum.

Now, Athenian students in their junior year spend twenty six days backpacking in either the Sierra Nevada during the summer, or Death Valley during the spring semester.

The course is designed to promote personal growth, develop a sense of community, and foster environmental stewardship amongst Athenian students.

In 2019, Athenian hosted their first FIRST LEGO League (FLL) tournament with the help of the Acropolis Robotics high school students.