I didn't vote but I'd probably give it a 4 because, I have no idea where the "trend" is. It probably has some meaning to you and the others who gave high marks but not to me so that's probably why you got some lower marks.
Otherwise it's a pretty good picture, just doesn't fit the challenge, to me anyway.
I gave you a 6. I thought the picture was well done - I can't find any technical flaws. I thought the connection to a trend was a little weak, but I was more lenient this week on that point, so that only counted it down a point or so.
I thought the picture was great and I'm sure your son loves it. The only flaw I could see with it was that the sunglasses were a little big on him. Personally, I thought it met the challenge just fine. My entry also got hammered for not meeting the challenge, though given the photo that got first place I'm a little confused about how people missed the connection in mine, as it was a similar idea. Well, as you said, and I enjoyed reading, you followed the "have fun" part of the directions, and that's what really counts. You should be proud of the photo, it's great.