C&C per req:
1. Nicely exposed and composed; good use of the curved shorline to lead the eye through the image. I would suggest a bit of dodging around the brush to image right foreground to lighten it up a little. Also consider a circular polarizer to eliminate the reflection on the water and emphasize the contrast between sky and cloud.
2. Fine technically, the subject doesn't do a lot for me however.
3. Very nice. Well executed image. My only niggle would be that the bright area in the background (roof?) is a bit distracting. A little tweaking in post would tone it down.
4. A tried and true idea, but in my mind this one just misses because of the different type of swing-seat in the background. Ideally patterns should be identical, repeating.
5. Very nice. Again good use of lines to lead the eye in. I think this one might have had good potential as an HDR, but has no issues as-is.
Just my $00.02 worth - your milage may vary.
~John