| Abbreviation | Definition |
|---|---|
| NNAT | Naglieri Nonverbal Ability Test |
| NNDS | National Network of Digital Schools |
| NNEC | North Nova Education Centre |
| NNHS | Naperville North High School |
| NNHS | Navotas National High School |
| NNHS | Newton North High School |
| NNHS | Newton North High School's |
| NNHS | Niles North High School |
| NNHS | Northern Nash High School |
| NNPS | Newport News Public Schools |
| NNSC | North Newton School Corp |
| NNSS | Nigerian Navy Secondary School |
| NOHS | Negros Occidental High School |
| NOHS | North Oconee High School |
| NOHS | North Oldham High School |
| NOHS | North Olmsted High School |
| NOMS | New Oxford Middle School |
| NOMS | Nicholas Orem Middle School, Hyattsville, Maryland |
| NOMS | North Oldham Middle School |
| NOMS | North Olmsted Middle School |