Well I don't think it should be emphasised heavily as it doesn't seem to help gay kids today who are bullied or harassed by other children all that much anyway (which is the goal, btw), but I don't think there is any evidence to indicate that telling children that it is "ok" to be gay makes any higher percentage of them have feelings that they wouldn't otherwise have.
In fact there's a lot of evidence that teaching kids it is not ok to be gay, and having societies that reflect that, causes a lot of devastation to those who are.
