The Children's Society is encouraging supporters to get more involved with the organisation through a new campaign section on its web site.
Stephen Blunden, director of fundraising and communications, said: "In recent years we haven't given supporters as much information as they want.
They've shown us that they are committed to supporting The Children's Society financially and now they're telling us that they want to get involved in the issues."
An e-postcard on the site depicts four prison scenes alongside the words Wish you Were Here. The card highlights the fact that while Parliament was in recess, hundreds of unconvicted children were in prison. It highlights the charity's Children Behind Bars campaign run with The Observer newspaper.
Supporters can sign the e-cards, which are then sent to their local MP.
The charity is also launching an email newsletter, Keymail, which will go to key supporters.