Good, and best at the primary end. There are three state primaries around here. There's one state secondary. Most schools across the county are rated good or better. The hard part comes when children reach eleven and the choice gets much narrower.
The three mainstream state primaries in the area averaged a maths score of about 107 at the end of primary school. The Gerrards Cross Church of England School is the one with the town's name on the gate, and St Joseph's Catholic Primary School and Robertswood School are on the same local list. With only three of them, a good year or a bad one at a single school moves that average quickly. The Department for Transport's 2019 modelling puts the average primary about 16 minutes' walk away, so most families can still walk this end of their children's education.
At secondary level there's one mainstream state school in the area, and its pupil-weighted Attainment 8 score is about 39. The Chalfonts Community College is the named secondary nearby. That makes the town's secondary figure one school's result, and the town's whole secondary reputation hangs on it. The same 2019 modelling puts the average secondary about 49 minutes away on foot, or 25 by public transport, which is far enough that families start comparing schools well before the application deadline. Gayhurst School is among the other schools on the local register for families who look beyond the state sector.
Ofsted has graded 80 of 94 settings across Buckinghamshire as good or outstanding, which is a little over four in five. Of those, 19 are outstanding, 11 require improvement and three are inadequate. Those counts cover the whole county, from Aylesbury to the Thames, so they describe the system the town belongs to more than its own few schools. The good ratio is real, though it was measured over a much bigger area than the walk to the school gate.
School places are allocated under the council's published admissions rules, so buying near a named school doesn't secure a place there. Listings that put "close to excellent schools" in the first paragraph have never had to answer to an admissions panel. Read the council's rules for each school you care about, and the most recent allocation outcomes, before you offer on a house for its school.
The schools are one of Gerrards Cross's real strengths, led by the primaries and backed by a county where most schools are graded well. The secondary picture is the one to read closely before you buy.