in my area the age is 4, however the child is fully responsible for the bird, no adult is allowed to touch, handle or feed the bird at any point, if the bird is too big or wild for the kid to get it into the cage another 4h'er can help, i have seen people disqualified. 4h shows get a really bad rap, the kids in my club have really nice birds, as do the leaders, we regularly show in bigger non 4h shows (last year the bantam nationals at the northeast congress) and often place really well not only in the junior section but also in the open division. We also have people with hatchery quality birds who show just for fun, they sometimes do well just because their birds are perfectly groomed and there aren't many other birds in the division, in any case i would encourage you to show and join the poultry club if you can, all the same rules as a normal show should apply, that means the birds must be pullorum tested and pure breeds unless entered in a production/mixed breed category. With hatchery birds 99 out of 100 will be poor quality when compared to the standard, but occasionaly there will be one that comes out alright. I'm not sure what the 4h program is like around you and i would encourage you to contact the poultry organizer or leader to get the details.