Thay depends on which certification agency you're going with. If its PADI then a 200 yd or 300 yd mask, snorkel, fin no stop swim (untimed), 5 min tread and 10 min float, a test, and show mastery on diving skills. There 5 confined water sessions and 4 open water sessions. Dive skills include:
mask clear (partial and full flood)
regulator clearing
regulator recovery
Alternate air source breathing
Deep water entries (giant stride, back roll, etc)
Snorkel clear
Snorkel / reg exchange
Surface swim with scuba
Bc oral inflation
Weight removal and replacement at surface
Deep water exit
5 point descent
mask removal and replacement
No mask breathing
Tired diver tow
Cramp removal
Neutral buoyancy
Air depletion/alt air source
Free flow breathing
Controlled emergency swimming ascent (CESA)
Hover
BC ditch and don at surface
Weight removal and replacement at surface
BC ditch and don underwater
Weight removal and replacement underwater
Then there's a few skin diving skills in there as well in any od the confined water "dives"
And I think that's about it with PADI. Others I'm not sure. I know NAUI encourages their instructors to teach beyond the standards and pretty much come up with their own requirements (i.e. longer swims, buddy breathing, some rescue, trim, so on, so forth).
With PADI, AOW is really like OW 2, it introduces different skills like, search and recovery, deep, wreck, drift, DPV, boat, etc. Some charters require advanced for certain dives, or at least record of experience with similar sitea/conditions.