On yes! 1st, 4th and 5th ftw!
The first just looks perfectly planned and executed like a photo for an advertisment.
The second doesn't quite do it for me. I think it's because the little boy's expression is less happy than the expressions he makes in the other photos.
The thirs seems a little too sad for this child as he seems to be waiting for someone or something. It's not a bad photo, it just seems to make the child more drawn away from the viewer.
The 4th is just cute as! I'm a big fan of minimal-clutter in photos and this one follows that. Just the boy and the swing, nothing else like trees, fences, cars, other people etc. His expression is just great. It really brings out the personality that happy children this age have.
The 5th is great but I'd suggest cropping it to only include the child and one or both of the swings. Obviously there's still going to be the white wall in the background even if you do crop it so cropping might not solve the clutter of the background. To me, you're either showing the child being in the surroundings or your focusing on the child's emotive expression. In this photo the child has a bewildered look on his face. I personally would have tried to get as much of that into the photo as possible, leaving the surroundings for another photo when the child looks like he's just sitting there looking at the sky etc (or something)
Keep it up 