Our older readers will probably remember "The Little Red School Book" which was published around 1971/2 and subsequently banned. It was banned in Australia too (which is where I'm from) although there was a censored reprint called "The Big Red School Book", which was magazine sized. I never knew exactly what was omitted, but certainly the entire sections about sex and drugs. In Blighty, the book has just been republished, supposedly in it's original, uncensored version, except it isn't. STRANGE THINGS ARE HAPPENING: NEWS - THE ONCE BANNED LITTLE RED SCHOOLBOOK RETURNS - AND IT'S STILL CENSORED

Links:
'The Little Red School Book': Sex Book Banned In 1969 Has Been Republished
Amazon

I was given a copy by my then girlfriend in 1981 (I don't know what she was trying to tell me!) and I still have it. I just checked, and the offending section is in mine.