Having already concocted an armorial of Britain’s universities, this year I moved onto the schools. The article at present is at least in a releasable state, although obviously it is not complete, and possibly never can be. There are, of course, far more primary and secondary schools in the United Kingdom than there are places of higher education, and probably a much lower proportion of them have acquired (whether by grant or assumption) armorial bearings. A major difficulty is working out what actually counts as a coat of arms, as many schools have logos designed in the traditional shape of a shield but with contents not blazonable, or not conforming to heraldic rules (e.g. faux quartering, overlapping charges, too much writing).
Geographic representation has also been a problem – I found way more shields for schools in England than in Scotland, Wales and Northern Ireland combined even accounting for population difference, so eventually had to split that country into its own page.
UPDATE (June 2022)
My illustration of the shield of Bangor Grammar School in Northern Ireland was featured on the Heraldry Subreddit. It was reviewed positively, at least compared to the other images in the same post, though it was primarily commenting on the design rather than my graphical skill.