ACFT LANDS AT A CLOSED ARPT.

Narrative

MY STUDENT AND I WERE ON A LCL TRAINING FLT WHEN THIS INCIDENT OCCURRED. WE FINISHED PRACTICING LAZY EIGHTS AND CHANDELLES AND NEEDED TO DO SOME SHORT AND SOFT FIELD LNDGS TO COMPLETE THE LESSON. WHILE WE WERE PRACTICING THE COMMERCIAL MANEUVERS; WE DRIFTED OUT OF OUR ORIGINAL AREA AND INTO ANOTHER ONE OF OUR PRACTICE AREAS. THE ORIGINAL PRACTICE AREA HAS THE CROOKSTON ARPT; WHICH WE KNEW WAS OPEN BECAUSE WE HAD THE CURRENT NOTAMS FOR THAT ARPT. HOWEVER; WE DRIFTED CLOSER TO THE WARREN ARPT AND ELECTED TO DO OUR LNDGS THERE. WARREN HAS 2 RWYS; 12-30 AND 4-22 (TURF). A FEW WKS PRIOR TO THIS INCIDENT; RWY 12-30 WAS CLOSED FOR RESURFACING. DURING THAT TIME; 4-22 WAS OPEN. RECENTLY; THAT RWY WAS REOPENED AND ARPT OPS THERE RETURNED TO NORMAL. AS WE APCHED WARREN; WE NOTICED THAT 12-30 HAD EQUIP ON THE RWY. THE RWY WAS CLOSED AND APPROPRIATELY MARKED WITH 'X'S ON THE THRESHOLDS. RWY 4- 22 WAS NOT MARKED SO WE ASSUMED THAT THE RWY WAS OPEN. MY STUDENT ELECTED TO LAND ON RWY 22 AND MADE HIS APCH ACCORDINGLY. WE EXECUTED A GAR DUE TO A POOR FINAL APCH. THE SECOND ATTEMPT WE DID A SOFT FIELD TKOF AND LNDG. ON THE 3RD TRY; MY STUDENT EXECUTED ANOTHER GAR DUE TO MEN AND EQUIP XING THE RWY. WE DEPARTED THE PATTERN AND I RADIOED THE FSS TO SEE IF THEY HAD ANY NOTAMS PERTAINING TO THE ACTIVITY AT THE ARPT. UNFORTUNATELY; THE BRIEFER TOLD ME THE ARPT WAS CLOSED. LATER; I FOUND OUT THAT THE ARPT WAS CLOSED THAT VERY MORNING (THE DAY BEFORE; IT WAS OPEN). SAME POSSIBLE CONTRIBUTING FACTORS TO THIS INCIDENT ARE AS FOLLOWS: 1) DRIFTING OUT OF THE PRACTICE AREA; 2) NOT OBTAINING CURRENT NOTAMS FOR THAT ARPT; AND RELYING ON PAST INFO; 3) LACK OF ARPT CLOSURE MARKINGS. POSSIBLE CORRECTIVE ACTIONS: 1) ALWAYS STAY IN THE ASSIGNED PRACTICE AREA; 2) GET CURRENT INFO REGARDING THE ARPTS I OPERATE ON; 3) BETTER RWY MARKINGS. I REALIZE THAT PAINTING AN 'X' ON A GRASS STRIP WOULD BE INAPPROPRIATE; BUT THE RWYS AT WARREN INTXN AND PAINTING AN 'X' ON THE INTXN OF THE HARD SURFACE (12-30) AND TURF (4-22) WOULD HELP SIGNIFY ARPT CLOSURE.