Sex education is extremely important and few would oppose that. The Danish and Icelandics do it very well and we should follow them. They're open, honest, pro women and pro children.
However, there's a world of difference between education and indoctrination.
Their insistence that parents should have no say on what their children are taught is typical of people who are trying to force a sinister agenda. It's nothing to do with the child's rights or education, it's about separating the child from their parents protection so they can be groomed and manipulated by abusers who want to force their issues on them.
There are groups with a long term goal to get rid of the age of consent by giving the children "sexual rights". This is why they're heavily promoting the transing of very young children who don't fit gender stereotypes. It's ultimately to take power of protection from the parents by threatening to take their kids if they don't participate in the manipulation of their child, threatening to take the careers of teachers and doctors who dare stand up to it, to make everybody scared to speak out because they'll be destroyed as a "hateful person"...
When everybody's silenced, they own your kids. Then they can say, if a fourteen year old can have a sex change, they can have sex... When they get that reduced, they'll say "but eight year old can change sex, why can't they have it?". There's an agenda. We can all feel it being pushed but it's a bait and switch.
I wouldn't let Tatchell or any of his associates near my kid, let alone provide a forced "sex" talk. What he has admitted in public about his opinion that young children aren't harmed and may even enjoy sexual abuse by adults, is disturbing. That says everything about him and the company he keeps.
The new buzz word in five/ten years will be peadophobe... You don't let me near your kid, you peadophobe. It sounds crazy now but unless this agenda is stopped, it's coming.