A message from UNESCO Bangkok: Every day, students around the world are denied the basic right to education because of bullying in school. Bullying particularly affects students who are perceived as not conforming to prevailing sexual and gender norms, including those who are believed to be lesbian, gay, bisexual, or transgender (LGBT). >>>
UNESCO has published the background document about homophobic bullying in schools, that was used during the international consultation held in Rio de Janeiro in December. It is an important document, giving quite a good overview.