A homework project that asks pupils to look out for lesbian, gay, bisexual and transgender characters in TV shows has been criticized by campaigners.
The project includes a bingo-style game where children are asked to cross off squares when they come across an LGBT character or reference.
The game encourages children as young as 11 to analyze how the media portrays same-sex relationships.
It is part of a series of teaching resources developed by the Sex Education Forum, which lobbies for compulsory sex education in all schools.
The Forum launched the game in its latest e-magazine for teachers in primary and secondary schools, which focuses heavily on LGBT issues.
The bingo game came under fire from campaigners who dubbed it an "inappropriate" homework topic.
Norman Wells, director of the Family Education Trust said: "This activity encourages pupils to focus on sexual characteristics and behavior to the exclusion of everything else.
"It also gives disproportionate attention to lifestyles and sexual feelings which are very much in the minority."
Wells stressed that the project would not be supported by many parents as it promotes an "unhealthy obsession with sex."
In what she described as a "radical" campaign, head of Stonewall, Ruth Hunt said, "a suite of books that celebrates difference in all its forms" could be commissioned by the group for under-5-year-olds.
Speaking to The Independent, Hunt claimed: "Loads of kids these days have two mums or two dads—or at least gay uncles and aunts."
Hunt was announced as chief executive at the end of July, having previously been deputy chief executive. She lives with her civil partner in London.