The Cougar mascot was chosen following a poll of the freshmen and sophomore students attending the new school in August 2000.

[7] In 2015, Vernon Hills was ranked as the 517th school nationwide, and 19th statewide, according to U.S. News & World Report.

The team came close to making the state finals their senior year, losing to Kaneland in the Quarterfinals.

[11][12] In 2020, the Cougars won their 4th straight CSL conference title, led by senior Jacob Gates.

The 2007–08 Pom Pons team won a state championship in the TEAMDance Illinois Class AA Open Dance category.

In the 2010 and 2012 season the Girls' Track and Field team won their IHSA AA Sectional.

[17] The VHHS music department has always performed very well at the IHSA state competition, placing 4th in its class in its first year of existence.

FBLA has had students place in the top 10 of Accounting at the National level for two straight years (2008, 2009).

[20] Ryan Kang, Kevin Yoon, and Neel Choudhary placed 2nd in state for "Computer Game Simulation and Programming", advancing to 2016 Nationals in Atlanta.

The Sophomore team had Ally Spence and Aiden Kang finishing in the top ten.

Junior/Senior 2 Person team of Justin Yim and Eric Zhang qualified for the playoff round and finished first in State.

The Frosh-Soph relay team of Aparajitha Adiraju, Kishore Iyer, Ari Bard and Ryan Curtis finished in 2nd place.

[23][24] The Worldwide Youth in Science and Engineering club at VHHS continues to be successful in their 1500 division.

In their first season with EIU, VHHS placed 3rd at the state level in the 1500 division with Nicolas Beaumont, Alexa Pomerantz, Itamar Shifrin, Rachel Liu, and Jeffrey Zhang placing in the top five for biology, chemistry, computer science, English, mathematics and physics.