The Citizenship Foundation is targeting all of the UK's 5,000 secondary schools in a bid to get record numbers of schoolchildren donating to charity during its national schools action week.
G-Week, which runs between 3 and 7 July this year, is part of Giving Nation, the web-based project for schools.
During the week, secondary schools are invited to download G-Week-themed lessons and assembly plans, and to organise fundraising, volunteering and campaigning activities.
Last year, 1,000 schools were involved in the initiative. The charity is aiming to involve more schools than last year by targeting every secondary school.
"The aim is to raise money and get children to think about citizenship," said Catherine Dawson, a spokeswoman for the foundation. "For example, last year some schools asked pupils to raise funds for one local, one national and one international charity to help them understand a range of issues."
The G-Week scheme invites schools to choose their own charities as the focus of their fundraising activities. This year, schools can enter an award scheme by recording their charity work in an online diary on the Giving Nation website, www.g-nation.co.uk.