It is a normal school designed to train teachers, helping them practice teaching styles shown by experience to be effective.
Joseph Lancaster opened the first model school in the English-speaking world in 1798 at Borough Road, Southwark in London.
It grew quickly to a thousand students, proving to be the prototype for curriculum, teaching methods and new provision that revolutionised schooling in Britain and the British Empire.
There certainly was. The first in the region and the Americas - one of the three earliest in the English-speaking world started as the Mico Institution, renamed Mico Teachers College, now Mico University in Kingston, Jamaica.
Hundreds of schools, including model schools opened during the colonial period. Beside Jamaica, Antigua and St Lucia were Mico centres for teacher training. There were other model schools also that anticipated a drive to educate more, if not all children at the time of independence.
A model school pioneers a curriculum, teaching method, new provision, a new approach to funding and/or some other prototype of schooling different from all other schools.
One is all-too obvious and invisible at the same time. Given the way the immediate post-independence generation of West Indian players rocketed to global cricketing supremacy, it is notable that no leader emerged to assemble the men who trained them in a Cricketing School for junior and teen primarily, and also, older players. The closest idea is the CLR James Centre for Cricket Research at Cave Hill Campus, UWI, Barbados and the High Performance Cricket Academy of the West Indies Cricket Board. Significantly, both these initiatives emerged, thanks to leadership by the eminent historian and (confessedly aspiring, but non-eminent) cricketer, Professor Sir Hilary Beckles.
The example of Sir Hilary Beckles cited in the answer immediately above suggests the answer to this question will be meaningful only after thoughtful study of four centuries in the Caribbean.