Going by what I've been seeing around the net in regards to ages/dates...:
1. Spock is born in 2232.
2. Kirk is born in 2233. Nero arrives.
3. Chekov is born in 2241 (he is no longer born in 2245).
4. Spock (actor was 12) beats up bullies in 2244.
5. Kirk (actor was 11) totals the Corvette in 2244.
6. Spock's rejection of the Science Academy appears to have been at age 17 or 18 (I take it it's the period in-between our notion of high school/college, which means 17-turning-18). That's 2250.
7. If Spock's a cadet for 4 years, he graduates in 2254. 2254-2258 are the 4 years that Spock programs the Kobayashi Maru.
8. Uhura enters Starfleet in 2254. Spock is Uhura's instructor for a time. At some point, they develop romantic feelings.
9. Pike intervenes and Kirk enters Starfleet in 2255.
10. The rest of the film happens in 2258.
