That is a big question that we often ask ourselves.
We conducted a major study to see what research said about that. As for entering immersion programs, the study showed that at the end of these early programs, oral results were normally somewhat higher than results in other programs. However with writing, we noted that immersion courses starting later yielded the same results.
Demographically speaking, we also discovered differences between children registered in early immersion and those registered in late immersion. For children entering early immersion, we noted more varied demographics, a more equal number of boys and girls, more socio-economic equality, and so on. With the late immersion programs, however, we noted that many more girls than boys participated.
As regards the number of children who went on to obtain a French-language diploma, we saw very little difference between children who completed the intermediary program and those who completed the early immersion program. The question is this: do the same type of students take the two programs? I think that the early immersion program contingent is somewhat more varied than the intermediate immersion program one.
We also discovered that many parents of children who participate in our programs are English-language learners, in other words, people who are learning English. We asked these parents what they prefer. We discovered that many parents who speak a language other than French and English at home prefer to register their children in the intermediate program, in order to give those children an opportunity to acquire a good grounding in English up until grade 3.
That is one of the reasons why our school board decided to create two points of entry. We wanted to give parents the choice. Some anglophone parents prefer that their children learn to read in English first, so that they have a very strong base. So parents are completely free to choose.