Clubs H-O
- Habitat for Humanity
- HEADstrong Club
- Help for the Homeless
- Helpful Hands
- Helping Hats for Helping Hands
- Heroes in Halos
- Highland Park Business and Investments Club
- Highland Park Clay Target Team
- Highland Park Esports Club
- Highland Park High School Italian Club
- Highland Park Ultimate Frisbee
- Hilites
- Hispanic Student Association
- HP Ambassadors
- HP Bass Team
- HP Bye Bye Bags
- HP Child Life Club
- HP Crew Club
- HP Cycling
- HP DKMS
- HP Engineering Club
- HP Games Club
- HP Latin Club
- HP Meals on Wheels
- HP Philosophy Club
- HP Rites for Children
- HP Robotics
- HP Student Recycling Committee
- HP Volunteer Council
- HP Women's Student Organization
- HPHS Service Squad
- HPHS Special Olympics Club
- HTRs Club
- Humans of Highland Park
- Ice Hockey
- International Thespian Club
- Investigations Into the Hidden
- Iron Sharpens Iron
- Italian Club
- Junior World Affairs Council
- Kindness for Kids
- Klife
- Kostumes for Kids
- Lacrosse (Boys)
- Lacrosse (Girls)
- Latin Club
- Litfest Club