You would enter the amount in Box 14 along with all of the other information on your W-2 in the W-2 input section of your Turbotax program. Please refer to the two Links below, for more information concerning the Maryland state pension:
http://comptroller.marylandtaxes.com/Government_Services/State_Payroll_Services/Static_Files/W2_Info...
https://ttlc.intuit.com/questions/2594177-i-contribute-to-the-md-state-teachers-pension-system-that-...
