I'm all for kids on allotments! My grandchildren come with me and they are learning about gardening and growing. However, they are always kept on my plot, and are made aware that they are not allowed to wander around. No way do they go onto anyone else's plot. They do not throw things, either. I think the main problem is not the children, but the lack of supervision. I certainly think that plotholders who damage other people's property or allow their children or visitors to do so should at least be warned, and if no improvement then maybe their lease should be terminated.