the national union of teachers has called for a ` positive portrayal of same sex relationships ' in lessons to be made ` compulsory ' under the next government .
it said mps had a duty to tackle ` homophobia , biphobia and transphobia ' in schools and create a ` positive climate of understanding about sexuality ' .
but critics accused the nut of ` thought control ' and said the intolerant ' proposals risked ` oversexualising ' children at a young age .