According to archival sources recounted in And Cheer for the Green and Gold, Chapin was an early feminist and suffragette who focused heavily on character development and intended the school to offer the same classical education as was available to boys of that era.

Each K class has two teachers, with regular use of teaching specialists (e.g., reading, Spanish, art, music, science, technology, gym, etc.)

Many students do independent studies or study abroad programs, particularly through Chapin's exchange programs with the St. Hilda's Anglican School for Girls (Perth, Australia) and the American Community Schools (Athens, Greece).

Since 2011, Chapin has worked with the Kibera School for Girls in Nairobi, Kenya, developing curriculum ideas and visiting each other's campuses.

Mentorship derives from multiple sources, including faculty advisors and peer leaders.

[5] While many Chapin students live on the Upper East Side near the school, others hail from other parts of Manhattan, as well as Brooklyn, Queens, the Bronx, New Jersey, Westchester, and Long Island.

Twenty-one percent of the students receive tuition assistance, amounting to over $5 million per year.

[6] Among the 21 Chapin activities are the student government (advisory), the student newspaper, the literary magazine, Amnesty International, the Gay-Straight Alliance, the Model UN, and groups dedicated to the study and performance of Classics, dance, drama, music, math, media, the environment, and science.

Chapin varsity sports include badminton, basketball, cross country, fencing, field hockey, golf, gymnastics, indoor track, lacrosse, soccer, squash, swimming, tennis, track and volleyball.

[9] Chapin has long stood in athletic rivalry to the neighboring Brearley School, with which it shares some classes, after-school programs, homecoming, and a robotics team.

The building features the two-story Annenberg Library with over 45,000 volumes and rooms for multimedia and video editing.

[17] With the project completed, Chapin now has eleven stories and a top-floor regulation-size gymnasium to complement its four previous gyms, a rooftop turf practice field and fitness center, expanded performing arts facilities, much larger dining facilities, and additional classrooms to provide more flexibility and experiential learning.

[18][6][19] Chapin's construction project drew opposition from neighbors, who have objected to its scale, its length, and the noise level, among other issues.

[21][22] An article in The Wall Street Journal ranked Chapin's college placement as third best in the country.