C172 instructor pilot reported a near midair collision while in the traffic pattern.

Attributes
ACN	1593551
Time
Date	201811
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	Landing
Flight Plan	None
Aircraft 2
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Person 1
Function	Pilot Flying Instructor
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Flight Instructor Flight Crew Commercial
Experience	Flight Crew Last 90 Days 46 Flight Crew Total 323
Events
Anomaly	Conflict NMAC Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Published Material / Policy Deviation - Procedural FAR
Miss Distance	Vertical 100

Narrative:

This was my first dual given flight. My private student and I were conducting landings to finish off lesson 15 at ZZZ. We came from practice area. The first 3 patterns were okay; traffic was not too busy and the flow was manageable. During these patterns; ZZZ tower was having a conversation with [another aircraft]; about performing 360 over [a reporting point] outside the class D airspace and how that could cause an issue with traffic coming into the airspace. When the conversation ended; at about my third pattern on upwind; I see a skyhawk over [another reporting point]; and the controller was yelling '[aircraft Y]; are you on frequency!' that crew replied; 'yes; we are;' tower replied; 'you entered the delta without contacting me.' I believe during that conversation; initially there was an archer heading southbound outside the pattern to enter traffic pattern for [runway] xxl. The crew's actions resulted in the pattern flow disturbed. The crew in the aircraft Z heading south turned and climbed into the pattern to avoid aircraft Y. We continued our upwind. By the time we were downwind; I saw aircraft Z above right us about 100 feet. I immediately reacted and descended. [A solution is to] increase situational awareness and stop teaching if I have to due to the business of congested airspace; and fly the airplane first to maintain safety of the flight.

Original NASA ASRS Text

Title: C172 instructor pilot reported a NMAC while in the traffic pattern.

Narrative: This was my first dual given flight. My private student and I were conducting landings to finish off lesson 15 at ZZZ. We came from practice area. The first 3 patterns were okay; traffic was not too busy and the flow was manageable. During these patterns; ZZZ Tower was having a conversation with [another aircraft]; about performing 360 over [a reporting point] outside the Class D airspace and how that could cause an issue with traffic coming into the airspace. When the conversation ended; at about my third pattern on upwind; I see a Skyhawk over [another reporting point]; and the controller was yelling '[Aircraft Y]; are you on frequency!' That crew replied; 'yes; we are;' Tower replied; 'you entered the Delta without contacting me.' I believe during that conversation; initially there was an Archer heading southbound outside the pattern to enter traffic pattern for [Runway] XXL. The crew's actions resulted in the pattern flow disturbed. The crew in the Aircraft Z heading south turned and climbed into the pattern to avoid Aircraft Y. We continued our upwind. By the time we were downwind; I saw Aircraft Z above right us about 100 feet. I immediately reacted and descended. [A solution is to] increase situational awareness and stop teaching if I have to due to the business of congested airspace; and fly the airplane first to maintain safety of the flight.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.