Object seen near my school 5-6 times over a three month period.

I work at an elementary school. My main job is teacher, but twice a week I am given other duties like watching the play ground in the morning. I first saw a sphere shaped object sitting in the sky completely still in October.
The sun is bright in Arizona, and unlike all the students on the playground I have some hiking sunglasses. I would catch a flash like sunlight reflecting off a metallic surface. Then I would observe the sphere which seemed to vanish as soon as I noticed it.
I want to add something about myself. I have always been able to detect when I am being watched. No matter the distance or situation. My fiancée says it’s my Native American DNA at work, but while on the playground I always would have the overwhelming feeling of being watched. Perhaps this is the reason only I seem to notice the sphere.
I never mentioned this to any co-workers. It seems the sphere would always appear at the same time in the same location.  I had playground duty Tuesday and Thursday. Sometimes I saw it on Tuesday and sometimes on Thursday. Never on both days in one week.  Taking a photo or video was extremely problematic. The sphere seemed to almost react to me raising cell phone at it by vanishing.
The new school year is starting and I will be on the playground again on Tuesday. Perhaps I will get a better image of the thing.