I can't find the actual [original] article right now, but you can Google news "boys schools" and probably find all the major articles on the topic. From the actual Ottawa Citizen article: a boy who literally says "I don't want to read about princesses." This is the sort of level the debate is being carried out at.
There's sort of two main categories of argument in support of "same sex schools". The first and most common is the always (with profound consistency) sexist and reactionary argument that "boys and girls are different", often even with clarifications to the effect of, girls like reading stories about princesses and doing what they're told, boys like running around and playing baseball and making stuff out of wood and such. This isn't simply to be discarded – it's to be fiercely confronted as an unusually reactionary statement with an unusually prominent and comfortable place in the public discourse.
It is worth considering that the “learning styles” (ie. sexist gender roles) virtually always attributed to girls are precisely those passive, subordinate positions granted both women (as an oppressed gender) and students within capitalist state schools, the latter designed as they are to mold young people to be obedient, productive workers under capitalism. (This latter fact isn't controversial if you're serious; the people who design and manage our education system tend to openly say it). Thus the perceived “better achievement” by girls is a response to the coincidence of their subordinate role with that of the student. This should be totally appalling to anyone concerned about human dignity, but so-called “progressive” individuals in our society are speaking not to simply maintain but to reinforce and reinvigorate it.
There is, however, another category of argument in support of same sex schooling. This latter category is considerably more sophisticated and tenable, but it's still extremely problematic. This is the category of argument that says, well, boys and girls are just uncomfortable together. Occasionally to this argument is appended some vague reference to “the hormones” (cf. “the uterus” and “hysteria”, but that's another topic). It's also quite similar, in form if not content, to the “reformed KKK” argument of – I don't mind black people, nothing wrong with black people, white people are great and black people are great, we just shouldn't MIX. If one does any survey of the white supremacist literature, particularly in modern times, this is by far the predominant narrative.
That's perhaps a digression though. There's nothing so SUPERFICIALLY reactionary in this argument as there is the former, and it's worth looking at seriously. Still, this is the argument that either men or women or both just can't function in the presence of the opposite sex. In some other sectors (although the continuing alliance between reactionary 'feminists' and openly anti-feminist groups make this sort of 'common front' quite common), this argument is given an obscene 'feminist' twist: girls are incapacitated under the oppressive gaze of male classmates. Part of the really troublesome thing about this is the inevitable small bit of truth to it. This truth, however, simply cannot be accepted at face value, and the implication that men have some metaphysical power to restrain women simply by their presence is an utterly nonsensical thing for anyone pretending to describe themselves as “feminist” to accept. Insofar as there is such a disruptive effect, to accept it as being anything other than contingent on a destructive society is to cede all terrain of meaningful struggle. It also needs to be pointed out that here the problem of sexism for girls is put not on sexist parents, provincial premieres, teachers, academics etc., but male peers.
Finally it's worth looking at the occasionally raised comparison with afrocentric schools. There is the immediate but significant difference that black people are legitimately oppressed, and that the education we have now actually is racist and white supremacist. There's also the significant difference that the afrocentric schools would be open to all students. Conversely, the bulk weight of advocacy for sex-segregated schooling is on the argument that boys, that male students are somehow oppressed in education. This argument rests implicitly and sometimes even explicitly on some conspiratorial fantasy about our education system being run by anti-baseball, pro-princess matriarchs. I'll even break with my usual position putting students ahead of teachers, and point out that this is often couched in a view that teachers, especially elementary school teachers, being predominantly women, are poor role models or managers of boys. It's actually analogous to, and although I haven't seen it probably shares some cultural resources with, the notion that boys can't be properly raised by single mothers. This too needs to be repulsed. While in general it's a good idea to degender both parenting and education (and note that the opposite is encouraged by the proposal), the idea that the problem as such is women being teachers (or parents) is profoundly insulting to women. Moreover, the idea that women actually run and organize the education system, according to some dominating feminine character, is completely ludicrous, but still heavily implied.
Back to the (counter)example of afrocentric schools, in that case there's an open recognition by almost all parties that the existence of afrocentric schools would be at best an uncomfortable state of affairs ameliorating particular conditions in an unhealthy society. There is rarely such a qualification in the case of sex-segregated schools, the idea that gendering schooling will somehow lead to an egalitarian utopia. When you combine all this with the inane conception of boys as oppressed by matriarchs, with the idea that boys and girls are just different – or actually quite importantly, that comfortable obedience to capitalist state schools is even a good thing anyway – the whole project is really dangerous, both materially and ideologically.
What, then, is the solution? It would be impossibly arrogant to say I know what “the solution” is, it's a lot just to try to describe the problem. But if the empirical fact of poor male performance in schools is the consequence, as I believe it is, of both an oppressive school system and an oppressive gender system – then the solution can't be a retrenchment of the former to buttress the latter. It has to be something which challenges both the essential nature both of schools as a capitalist state apparatus – and a gender system which renders women in general obedient and deferential and a few (ruling class) men extraordinary power.