General aviation flight instructor on a training flight reported a near miss with a possible UAS during cruise and in controlled airspace.

Narrative

While on a training flight under an IFR flight plan; my student and I came close to striking what appeared to be a small balloon or drone type device. The conditions were daytime VMC with sky clear; however the in-flight visibility was degraded due to haze across the valley. We were returning to our home airport and flying direct to NTELL intersection at the time of the incident. The object was situated at 5;000 ft MSL approximately 5 NM northwest of MAE; near Highway 99. It was mostly silver or gray with a short rope or cable carrying what seemed like a dark rectangular box/device. I could not tell if it was also tethered to the ground. Upon seeing the object very close to our wing out to the left; I immediately took controls from my student (who was under a view limiting device at the time) and started a bank to the right to increase separation distance. After we passed by the object; I gave controls back to my student and attempted to look back to get a better idea of what it was. I then contacted FAT Approach with the approximate location; altitude; and description of the object. I do not believe I could have done anything different to prevent the near miss; as there had been no previous reports about the object; there was no way to see it on the ADSB-In; and the haze made small objects difficult to see.