Vicky Tuck, principal of Cheltenham Ladies' College, said she found the economic downturn 'bracing' and hoped it would lead to the end of a materialistic 'me, me, me society'.
Mrs Tuck was speaking at the start of the Girls' Schools Association's (GSA's) annual conference - representing 200 fee-paying girls' schools - in Winchester, Hampshire.
She told delegates that parents today were anxious that their daughters were growing up too fast, and were worried that they are exposed to many negative influences.
Mrs Tuck said: 'Sometimes, surrounded by media reports on Botox and bingeing, it's easy to feel we lead in a moral vacuum, garden in a gale. But we must go on gardening!
'Am I alone in finding the economic downturn somehow bracing? Perhaps it will spell the end of the conspicuous and ultimately unfulfilling materialism of the me, me, me society. Let's hope so.'
Mrs Tuck said school communities were the 'antidote to self-absorption and narrow-mindedness.'
She said that 'prolonging the wholesomeness of childhood' is often cited by parents as a key reason for choosing a girls' school.
'Parents are worried, aren't we all, about a coarsening of society and the toxic cocktail of binge drinking, internet safety and the early sexualisation of girls,' she said.
Mrs Tuck said the GSA would be launching a new website in January, mydaughter.co.uk, to give advice to parents on raising girls.
Mrs Tuck also told delegates that it was 'good risk management' for every independent school to consider the possible impact of a recession.
But she added: 'Maybe there are costs you can cut, but don't dilute the essence of what your schools do that make them distinctive enough from the state provision that parents feel that their investment is justified.'
Mrs Tuck's speech also addressed single sex education, and the importance of teaching girls differently to boys, Daily Mail reported.
She said girls' brains were 'wired differently' and that it was 'crucial to cater for their separate needs'.
She said: 'I have a hunch that in 50 years time, or maybe only 25, people will be doubled up with laughter when they watch documentaries about the history of education and discover that people once thought it was a good idea to educate adolescent boys and girls together.'