Here's what passes through my mind.
Photo One - I really like the way the red pops out. The lines are interesting, and curve nicely. The background does make it seem a little 'busy', but it's still good.
Photo Two - Some really nice shades of green, and I like the way the tree trunks going upwards convey an impression of straight lines without actually being straight. A nice nature shot, but it's probably a little too dark for my personal tastes.
Photo Three - What a wonderful image! I like how the colours are slightly muted. It's bright, but there's an absence of light that works here. Despite the season, the balance of the dark leaves gives it an almost autumnal feel. Doesn't really fit the theme so well (other than the beak), but I do really like the photo.
Photo Four - That's a cute little pencil holder! Sadly, it's a bit out of focus, and doesn't really work for me so much.
Photo Five - Really nice macro shot. A good idea, and I like the contrast between the colours, the cream/white controller and the black background. My only potential peeve with an excellent shot is that it would perhaps be cool to have the focus more towards the back of the buttons, on the yellow (primary) button as opposed to the green. Or possibly pull the analogue stick back to remove it appearing as somewhat of a blob. Either way, it's a great photo.
Photo Six - I agree with the person who said it's reminiscent of a wood carving of some form. Bold red colours give it a good atmosphere.
Photo Seven - I really love this, but have no bloody clue what it is! Fantastic abstract!
Photo Eight - Excellent 'pop' from the red to the bold blue. I'm not certain about the little stick figure, but it does have a certain quirky charm.
Photo Nine - I love the composition of this. All of the balls have excellent colour (though the blue does blend in slightly with the table). I love that the cue is in there, and the white ball too. I actually like the pocket being in the corner too... added with the cue/white, it gives it a feeling of action, despite it being static.
Photo Ten - D6, D8, D12, D20... no D4? A fun picture. Not too evident in terms of primary colours, per se, and perhaps a little dark for some of the colour to stand out, but that does accentuate the lighter ones. I like it.
Photo Eleven - Haha! Did you actually sort those yourself? Are you a roadie for a famous rock band?
It's visually striking, especially the yellow, and having the mixed bowl in there works really well. Perhaps for teh theme, given that the yellow is the only strictly primary colour, you could have had the brilliant yellow bowl on its own next to the mixed bowl? As in primary vs non-primary? Just an idea... I like this one too.
Photo Twelve - A smart idea, and the colour segregation works, but it seems a little out of focus. I would have preferred it to be in focus.
Photo Thirteen - I half love this. The colours are wonderful. The blue and yellow especially, but the use of primary colours works well. Also, the items used are fantastic. A really interesting composition... however, the red colours is totally 'blown out' on the rose, and we lose the details of it. Also, I have no idea what the scientific looking thingy in the backgroundis, but it distracts from the items focused on.
Photo Fourteen - I really like this take on the theme, and having the three different colours of flower together is a great idea and a good shot. I think perhaps getting closer in might have made it more dramatic, but as it stands it's a nice shot.
OverallI'd say that it's between 5, 7, 8 and 9 for me... but I plumped for 9 in the end, for the overall composition.