my AEA code has been 'L' for a long while. and i just talked with my carrer counsler recently about request the assignment that i want go. Now, my AEA code is 'M' now. so my question is, is that means he put me in the system already to request the place i want to go ? thanks

AEA Code "M" means that you are pending a RETAIN System transaction, so to answer your question yes it means he has put something in the system for you. For future reference you can find all AEA Codes and what they mean in AR 614-200 Chap 3, Table 3-1

Good Luck, hope you get the assignment!!!

I have a M code and for me it stands for reclassing, L code means on assignment restrictions and W means stabilation.
Goto ASK in AKO and under PDL tab and i believe its the tab that says mos or personnel and it will tell you whats happening and also gives you a break down on all aea codes. PDL reflects what HRC has in the system for you. ASK is down right now so i might be a little off.

So basically what I am understanding, is that if I have a school lined up for that I re-enlisted for in August of 2010 I should have a M instead of an L.

This is what the regulation states the "M" AEA Code means exactly:

Soldiers stabilized while awaiting a RETAIN System transaction for reenlistment or undergoing reclassification. This code
will terminate upon completion of reenlistment and/or reclassification action.