This paper derives from research that had the aim of understanding more about adolescents' views of sex education and adolescent sexuality. The data are taken from three separate pieces of research conducted in 1984, 1998 and 2003. This paper presents data about gender, information and knowledge relating to sexuality. It seeks to demonstrate that attitudes to information and knowledge vary significantly with gender. The data suggest that many adolescents we studied were offered different access to information about sex and sexuality in their families. The argument is that this has impact on the sources of information that they rely upon and prefer. We investigate the underlying issues about the ways boys obtain not only information about sex, but also their attitudes to sexual encounters. Sources of information and counselling about sexuality varied with gender. Boys and girls were exposed to different kinds of experience, in which information about sexuality and messages about desire also vary. Home and intimacy with parents, especially mothers, is important for many, although not all, girls in a way it is not for boys. This indicates a picture of boys learning about sex and sexuality in ways that by and large do not include adults, or more especially trusted adults, and where there appears to be some elements of exclusion from the family. This has important implications for sex education programmes, and may offer us insights into why the boys resist school sex education work. (Contains 2 notes.)