Looking for web-based booking system for summer campus

[x]

I'm looking for a "summer camp" booking system for a non-profit organisation.
We want to run the booking system on our own (Linux) webserver.
Searching I have found quite a few systems for booking meeting rooms, like MRBS http://mrbs.sourceforge.net/
However these doesn't quite meet our needs, therefore I'm asking around.

A little more details:
The organisation lets kids spend a week on a summer camp training football or swimming or basketball or whatever.
People have to book and pay a fee in advance.
So it's like this:

Week 25, 26, 27
Football-camp for ages 8-12, 12 kids / week
Sailing for ages 12-16,  14 kids / week
Week 27, 28, 29 
How-to-skin-a-cat-week, ages 6-17, 24 kids / week

...etc..
Also would be good but not necessary with possibility to book material & playground - canoes, tennis yard etc - per the hour.
And as it's for kids, it must be possible to make several bookings under one account, for all kids in a family.

And last, it doesn't have to be free, we don't mind paying for it - as long as we get complete control no renting!

[mwv10]

Not much available for free, have you considered saas? Something like booking wiz or smartbookings