No, he did not provide any evidence. But he has a well-developed hate against religions and so draws the conclusion that they educated them to get more followers. He stated that he thought that the monks forced the children to meditate. Please note that the period of interest is early 20th century.
The only thing I've been able to find is this(so I guess it was Thailand): http://en.wikipedia.org/wiki/Buddhism_i ... and_clergy
& http://www.hellosiam.com/html/thailand/ ... ligion.htm
"As in medieval Europe, most early Thai scholars were clerics whose major monastic activity was to teach the unlettered. Behind the quiet facade of monastic life, many village boys learned the rudiments of reading and writing Thai and Pali, simple arithmetic and the Buddhist precepts. Education was primarily concerned with ethical and religious instruction. Because most early Thai literature concerned religion, literacy allowed greater participation in religious life.
Although the Department (later Ministry) of Education was founded in 1887, monasteries remained centers of basic education until nationwide primary education became compulsory in 1921. In many remote areas today, monks conduct daily classed for village children. "
It would be very interesting to know if Pali was taught in the early 20th century and if the children still learned their language through religious texts by then. Considering the kind of literature that one expects to find in a monastery, that could've very well been the case. If it was so, it would be just as interesting to know if this was because of a lack of any other literature, a "what we have will do"-mentality or if it was on purpose, in order to teach Buddhism at an early age.
As for non-Buddhist children receiving education, I've been unable to find anything what so ever. My guess is that it was very rare, if not non-existing. A qualified guess would be that the church/mosque/whatever educated the children in a similar way, if the family was unable to afford any other education.
Of course we also have to take into account that Thailand in the the '20s was way different from now. And schools in Sweden(where I live) had children read the bible during the same period. I think it's rather safe to conclude that you were kinda stuck with the religion in the country you were born in.