I'll go first:

18 - Finished school and was able to drink in pubs (:D) Social life at its best. The girl I fancied at school broke up with her boyfriend (:D). I confessed my feelings of attraction towards her. Unfortunately, I made a complete fucking mess of it and she permanently blocked me on Facebook - but it was the only way of me getting over her, tbf. No sense of impending educational-related doom round the corner. Started dabbling with MDMA, which signalled the decline into age 19, but otherwise, this was the best year of my life. It was also the year I discovered Radiohead and became a lifelong music fan. I still am this age, psychologically.
9 - First year at a new, strict religious primary school. Teachers were horrible but otherwise my playtime/schoolyard-life was super-nostalgic, and as fun and carefree as it'd ever get. It was also the year I first got a games console AND discovered Pokemon Silver, essentially spending the year playing it. Also made some friends for life.
15 - Doing well at school. Future looked bright. Had no social life but all I cared about was grades. Power felt like it was finally in my hands. The girl I secretly liked was still single. It was also the year I completed Ocarina of Time. For me that was a good enough reason to claim I'd lost my virginity.
14 - First year of 'upper' school; the start of GCSEs. No more bad grades: this was a clean new slate for me to start all over again. Noticed a girl in several of my classes, who I eventually developed a crush on. It was the beginning of some horrible unrequited love, but overall it was a nice, emotionally healthy, innocent period of time. I'd be content if every year of my life was up to this level.
6 - The Christmasy/Summery year. Broke a bone and missed lots of school, but became popular. Everyone in my class was my best friend. And it was 1998!
11 - First year of secondary school, wasn't bad actually.
5 - First year of primary school. For some reason I was put in the same class as 7 year olds. Intimidating. Also wet my pants in P.E.. Humiliating. Apart from that, the memories are to die for.
7 - Moved into the 'smart' class primary school with 'thick' kids from the year above. Noisy bunch of pricks. But it was the beginning of a new millennium, and it felt like the start of something new and magical. Can't say I feel the same way in 2014 :/
16 - Mixed feelings about this one. My classes at school changed and the girl I secretly fancied was no longer in any of them. She started going out with someone else which caused me a lot of depression, and was essentially the downfall of my life. Grades slipped enormously; rapidly went from 'sensible well-behaving high achiever' kid to 'smoking outside the Maths block, hoping to pass the year with the skin of my teeth' kid. To neutralise this pain, I got a proper social life outside of school and started drinking, and having some good times. Half good and half bad.
20 - It's been a tightrope of having a horrible time in halls and getting drunk loads. Felt old for the first time. Really good and really bad.
10 - Got teased by my so-called friends in the final year of primary school. As we were coming close to entering secondary school, everyone in my class pretended to be 'rebels' and listen to bands like Nirvana and Red Hot Chili Peppers, which I didn't. The first year in which I started feeling 'weird', and 'different' from everyone else.
19 - The Wilderness Years. Things were a bit ropey, and it was the loneliest I'd ever felt up to that point, but I still had friends and access to alcohol, so it was an adequate time to be alive. Plouged through and got to university eventually.
17 - Nothing happened in this stretch of time. Nothing at all. The relationship of the girl I fancied and her boyfriend persisted. Would they break up? Would I ever be able to confess my feelings of attraction towards her? The purgatory year.
8 - One of the shitter years at primary school. Experienced some really bad friendship bullying from this new-ish kid who tried to 'reclaim' one of his best friends from me - stating that he actually knew him before I did and was even born in the same hospital room as him - and tried to exclude me as much as possible. Was in the process of moving house to a different school too, which was distressing.
13 - Another miserable year in which that Joe made my life hell. Still, it was a turning point - the point at which I cared about school and studied hard - a habit which would eventually pay off.
12 - Second year of secondary school, got bullied by some kid in my class named Joe who made my life hell for the next 2 years. The first really bad year of my life.
21 - This has been the worst year of my life, a total shock followed by nothing but doom and paranoia, and the expectation of things to get worse and worse as I find myself getting closer and closer to the centre of Hell. Basically had a nervous breakdown, and spent the rest of it trying to recover. If there was a soundtrack for it, it would be Pornography by The Cure.

Didn't intend to spend anywhere near as much time on this as I actually have.