If they're surrounded by gays and lesbian, then a man with a woman in a relationship is considered 'abnormal'!! What kind of a society would we have then??
Exactly what i was saying spikegifted, except you have worded it much better

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I suppose there is no such thing as the norm or normal as everyone is different, i suppose it would be better calling children or people who are similiar, "alike" or "the average".
But in a school full of gay children, a child would see the average as the children and teachers around them, and this will not help them when they leave and go into society it would be a artificial environment like living in a bubble, who knows what problems it would cause for them later in life? a hard question to answer i think.