This paper examines some of the many senses of 'privacy' and its justification as an important value in a liberal society. It argues that the basic idea is that for a sense of personhood the individual must have an area of her life which is 'her own' and not to be invaded without her consent. In this sense, privacy is a universal human value, but, of course, the form it takes may vary from society to society. This basic areas of privacy are: (1) One's inner life (thoughts etc.) and the external manifestation of these (such as intimate diaries). (2) Physical privacy, as in one's home, or, even more so, one's bedroom. (3) In public places where invasive techniques are used (e.g. hidden cameras, binoculars, telescopic sights). The analysis is then applied to children. While conceding that, because of their immaturity, children may sometimes be entitled to less privacy than adults, it is important to remember that they have to learn the values associated with privacy and hence ought to be accorded as much privacy as possible. This is then related to schools, which are particularly problematic, since schooling between certain ages is compulsory. There is a practical discussion of the limitations which privacy imposes on: school rules, research on children in classrooms; handling of personal belongings; diaries and personal notes; school record-keeping; and assessment practices.