Large Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 9.5
Distraction; Confusion
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Air Traffic Control Separated Traffic
Company Policy; Procedure
Aircraft X on vectors to final RWY 35R OKC from DECKK leaving 15;000 for 6;000 as per the 'flow.'   My co-worker initially assigned 6;000 to Aircraft X but suggested amending altitude reference unknown but suspected VFR flight school traffic.  This traffic is well known and flies in the area daily.  What is unusual is that this unknown traffic was much higher than usual.  The aircraft was maneuvering between 5;000 and 7;000 feet.  I stopped Aircraft X's descent and turned him NW bound away from traffic.  As I did this unknown traffic turned west also causing conflict again.  I issued traffic to Aircraft X at least twice.  He saw the aircraft and was able to once again turn and descend on course.  A third co-worker watched the unknown target become identified by OUN Tower as Aircraft Y.  We never had any contact with this unknown aircraft.  About 10 miles later he once again came into conflict with a second unknown but suspected aircraft maneuvering 12 south of OKC on final RWY35R.  This aircraft was just outside of the Class C but inside of the associated outer ring.  Aircraft X saw the traffic and once again adjusted his flight path to avoid traffic.  Aircraft X spoke to the OKC Tower Controller about the VFRs after landing but did not contact the TRACON.Inform flight school of the danger of maneuvering in this area when multiple aircraft are inbound to OKC final and OKC satellite airports.  This is a constant problem with airlines and other GA aircraft performing TCAS/RA maneuvers or being vectored away from VFR practice area aircraft causing delays to air traffic.  Suggest to the flight school to either call for flight following; fly at a lower altitude or maneuver elsewhere.  This is not illegal; but highly dangerous.  This happened two other times today.
OKC Arrival Controller reports of VFR traffic from a flight school getting in the way of the arrivals coming in to the major airport.