Examples from the Web for free school
The mother could not read nor write—'worse luck,' as she said; her only chance of educating these children was a free-school.
And it is not unlikely that the Poet may, at some time, have been an assistant teacher in the free-school at Stratford.
He built a free-school at Ulfrunehampton in Staffordshire, etc.The Survey of London|John Stow
I went to Tunbridge, to see a solemn exercise at the free-school there.The Diary of John Evelyn, Volume II (of 2)|John Evelyn
But, I should say he belonged, if anything, to the free-school system.The Confidence-Man|Herman Melville