| Abbreviation | Definition |
|---|---|
| HASD | Hamburg Area School District |
| HASD | Hazleton Area School District |
| HASD | Hempfield Area School District |
| HASD | Hollidaysburg Area School District |
| HASD | Hopewell Area School District |
| HASD | Hortonville Area School District |
| HASD | Huntingdon Area School District |
| HASG | Haberdashers Aske School for Girls |
| HASS | Higher Academics Summer School |
| HAT | Homework, Attendance, and Tardies |
| HBA | Hawaii Baptist Academy |
| HBAS | Huntington Beach Adult School |
| HBGS | Helsinki Biomedical Graduate School |
| HBHS | Hamilton Boys' High School |
| HBHS | Hampton Bays High School |
| HBHS | Helen Bernstein High School |
| HBHS | High Bridge High School |
| HBHS | Hokes Bluff High School |
| HBHS | Hollis Brookline High School |
| HBHS | Hudson's Bay High School |