What organised sporting activities (tennis, baseball, cricket) are there for 5 and 7 year olds? looking for something to enrol my boys, prefeably in the East or District 15.

yeah. I think there are quite a few choices bro. If it's football, you can check out the football academies. There's one at macpherson from the Arsenal soccer school. I only know that one because I play at that pitch lol. But every Thursday night, you can see the kids train. So you might wanna check it out first-hand?