On May 15, 2019, about 1915 central daylight time, a Piper PA44-180, N39693, was substantially damaged when it was involved in an accident near Centralia, Illinois. The flight instructor and pilot receiving instruction sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. After about 2 hours of uneventful flight, the pilots were returning to the airport for landing. While performing the Before Landing checklist, the instructor and pilot receiving instruction noticed that the nose landing gear light did not illuminate. Utilizing the landing gear mirror, the instructor could see that the landing gear door was open, but he could only see the nose landing gear tire partially extended. They flew the airplane to a nearby practice area and the pilots performed the inoperative landing gear checklist. The instructor attempted to extend the gear with the emergency extension system, but the nose gear did not extend. The instructor then attempted maneuvers to extend the nose landing gear; however, the gear did not extend. The pilots returned to the airport and landed in a grassy area parallel to the runway. Upon touchdown, the nose dug into the soft, wet ground and the airplane came to rest inverted, resulting in substantial damage to the fuselage and empennage. Postaccident examination of the nose landing gear system and emergency gear extension system did not reveal any anomalies that could have resulted in the failure of the nose gear to extend; however, a detailed examination of the system was not possible due to the extent of the impact damage.