My daughter has just turned 5. She is a fantastic kid, but her boundless energy puts a lot of people off her and I find it very difficult to get a babysitter more than once. She's not naughty, just energetic.
No, I'm not in denial. She isn't an angel by any means. And we don't get along all the time. Her behaviour for many years was atrocious, but I've had to learn to focus her energy.
I've recently started buying things that she is really interested in, and taking away all the toys that amuse her for a brief moment in time. She has a trampoline that she can jump on for up to two hours at a time. It takes some preparation before we can do anything, including going shopping. Even getting ready for school can be a battle of wills while she flits from one thing to another.
Recently, like in the last 2 months, I've got the energy even more under control by cutting off contact with my parents. She used to see them every day and her energy levels and bad behaviour always spiked after she'd seen them. So I've limited their access to her to only Saturdays. I find that she focuses a lot better and is less likely to be running all over the place destroying things and screaming at the top of her lungs as she tries to bathe the cat and catch the chooks etc.
I basically had to sit down and keep track of the times when her energy levels spiked, and then assess what had happened right before. She's been taken off all artificial colours, flavours, preservatives as well - that helped enormously when she was younger. Now it really is more behavioural than chemical. You can try changing diet. We took her off everything and reintroduced certain one at a time to figure out which foods set off the destructive mechanisms.