[7] In 1995, increased enrollment (2600) forced it to go with a split day, starting freshmen (9 AM) two hours after upperclassmen (7 AM) which would continue for the next two years.

This continued to increase, forcing the addition of 14 trailers in 1996 to accommodate the students in a school designed for 1800.

[9][10] Competitive sports at Chattahoochee include baseball, basketball, cheerleading, cross country, football, gymnastics, lacrosse, soccer, golf, tennis, track, volleyball, and wrestling.

The Lady Cougars defeated four-time defending state champions, the Milton Eagles, to take home the title.

[11] The Chattahoochee High School football team had its first season in 1991, competing in Region 6-Division AAAA, the highest classification at the time.

For the 2010 season, the Cougars were moved down to AAAA since the opening of Johns Creek High School pulled many students away from Chattahoochee.

The Cougars met the undefeated Starr's Mill Panthers at the Georgia Dome for the state championship.

The boys' swim team won the GA High School State Championship in 1996 and 2023.

Chattahoochee produces a literary magazine called Chrysalis that features art and writing by its students.

The pavilion is positioned as an overlook to the Arena and has hosted numerous pre-game activities such as cookouts and booster meetings.