My instructor said that the max xwind speed for a safe landing in a 152 was 12.5 kts
Hmmm, first of all your FI is wrong. The safe maximum crosswind speed for a 152 when landing is the speed at which the pilot is able to make a safe landing. Some people will not feel happy with say 6kts, others will be perfectly happy with 12kts. There is also
NO crosswind limit for a 152. There is, however, a
DEMONSTRATED CROSSWIND COMPONENT, which Cessna stresses is
NOT a limit, and this is 12 kts. Ask your FI to let you read the aircraft's POH where you will be able to read this for yourself. Your FTO may have its own limits which it requires you to adhere to. Read what everyone else has written, there is a lot of good advice in there. I was very fortunate in my FI who taught me how to do crosswind landings from the outset. For those who may be inclined to think I mean the full 12kts across the runway, or that I was pushed beyond my limits, I don't. I mean that if there was a crosswind when it came to landing then we didn't ask for a runway change, I was guided through it with as much or as little help from the FI as necessary to make a good, safe landing.