Large Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Communication Breakdown; Confusion; Situational Awareness
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors
Leading up to the event the developmental had the airspace under control; was providing appropriate spacing and sequencing of aircraft to the primary runway.  We are in the process of teaching/learning how to look at all of the airport's traffic situation and make plans and decision based upon the needs of the airport.  Developmental had really grasped the intended lesson; and was providing excellent spacing.  Varying his plans based upon not only his traffic; but the traffic of our North Arrival counterpart and traffic still inbound the airport.  Developmental showed advanced thinking; and I truly feel had a break through in his training.All of that preceded a supervisory change.  As soon an FLM X took control of the room he immediately started changing aircraft runway assignments.  Changing plans; and distracting the developmental to a point that he pushed away from the scope and said he could no longer work the traffic.  Airspace that was once under control erupted into a storm of aircraft in the 'wrong' place to make the supervisor's plan work.  In my haste to make the supervisor's plan work; Aircraft X exited my airspace and entered ACY approach control's airspace without a point out.   The aircraft was 'forgotten' or overlooked in my sweep.  This happened because one of the developmental's techniques is to turn an aircraft blue when the aircraft 'needs something' whereas to me a blue aircraft means 'handed off and frequency changed'.  I failed to recognize the problem until it was brought to my attention about 7 miles southwest of VCN. Let controllers work. Let developmental learn. Let instructors instruct. Intervene only when SAFETY requires; not when things aren't the way you would do it
TRACON Controller providing OJT described an airspace incursion when the FLM directed an alternate plan of action differing from the intentions of the controllers working the position.