| Casterton School | |
|---|---|
 | |
| Location | |
 | |
| , , LA6 2SG England | |
| Coordinates | 54°12′42″N 2°34′30″W / 54.211667°N 2.574964°W |
| Information | |
| Type | Private day and boarding |
| Motto | Cor Unum Via Una (One Heart, One Way) |
| Religious affiliation(s) | Church of England |
| Established | 1823 |
| Founder | Rev Carus Wilson |
| Closed | 2013 (absorbed by Sedbergh School) |
| Local authority | Cumbria |
| Gender | Girls; Boys (3-11) |
| Age | 3 to 18 |
| Enrolment | 300~ (2013) |
| Houses | Dobson Vincent Beale Williams Harben |
| Colour(s) | Blue |
Casterton School was an independent boarding and day school for girls aged 3 to 18 years in the village of Casterton in rural Cumbria. In its final years it also admitted boys, up to the age of 11. The school ceased to exist in 2013, though a preparatory school remains on the site. It merged with Sedbergh School, whose junior section now occupies the campus while Casterton's senior school pupils moved to the Sedbergh site.