Schools
| Name | Category | Notes |
|---|---|---|
| Ammanford Grammar School | Grammar | |
| Ammanford School | Other Private | |
| Ampleforth College | Public School | |
| Anderson Institute, Lerwick | Miscellaneous | |
| Andrew Cairns Secondary Modern, Littlehampton | Secondary Modern | |
| Annadale Grammar School | Grammar | |
| Annan Academy | Miscellaneous | |
| Anniesland College, Glasgow | FE College | |
| Appleby GS Westmorland | Grammar | |
| Apsley Grammar School, Hemel Hempstead | Grammar | |
| Arbroath High School | Grammar | |
| Archbishop Holgate's Grammar School, Barnsley | Grammar | |
| Archbishop Holgate's GS York | Public School | |
| Ardingly | Public School | |
| Ardingly College, Brighton | Other Private | |
| Ardrossan Academy | Grammar | |
| Ardwyn Grammar School, Aberystwyth | Grammar | |
| Armagh Royal School | Other Private | |
| Armstrong College, Newcastle-upon-Tyne | Other Private | |
| Arnold House School | Public |