Almost a decade after same-sex marriage became legal in Canada, a new report shows that similarly liberal views are yet to filter down to schools.
Researcher Catherine Taylor of Winnipeg University found that about half of gay high-school boys reported being subjected to verbal abuse and a quarter feared for their physical safety.
But even more shocking was the treatment handed out to gay girls, Professor Taylor said.
Despite 80 per cent of schools having anti-harassment policies, lesbians were twice as likely to suffer physical bullying compared to gay boys, Professor Taylor found.
More than half of gay girls said they were subjected to "mean rumours", more than six in 10 said they felt unsafe at school, and a quarter said they skipped school because of the situation.
The study, Every Class in Every School, surveyed 3,700 students from all parts of Canada. "These numbers, sadly, were consistent from one end of the country to the other, in rural and in urban settings," Prof Taylor said.
In one school, a lesbian student reported having a binder thrown at her by a male classmate who called her a "dyke". Later, a second male classmate told her that he would "fix her problem".
Despite growing acceptance of gay culture and gay celebrities, the study found that traditional insults such as "dyke" and "lesbo" are still common.
While teachers might intervene when they hear those words, said Professor Taylor, they ignore homophobic students and others who have redefined the word gay to mean stupid or ugly, as in: "That sweater's so gay!"
According to Helen Kennedy, president of Egale Canada (Equality for Gays and Lesbians Everywhere), students hear the phrase "that's so gay" as often as 75 times a day. And since it is used as a pejorative, it tells them that they are "less worthy".
More study is needed to determine why lesbian students are at such risk, according to Ms Kennedy.
"There is a lack of role models in the curriculum," she said. "Homophobic boys react to lesbians and bisexual girls in a misogynist manner, and we think that girls who assault lesbian and bisexual girls are reacting to these girls' decision to be `out'."
The study also found that children of gay parents were affected by homophobia. Forty per cent reported feeling unsafe at school, compared with 13 per cent of the general school population. And 50 per cent said that teachers made off-hand homophobic comments.
"There is, however, a reason to believe that things can change," says Ms Kennedy. "Fully 58 per cent of non-LGBTQ (lesbian, gay, bisexual, transgender and questioning) students report being upset by homophobic comments. This means that if they are given the opportunity to stand up and speak out, the school climate can be made safer for everyone."