Alright: I bet folks don't see this one coming:
THE WEEKEND 'FLYING LESSON':
You can tell, if you try, which small aircraft are involved in some sort of 'meandering / loitering flight.
(Aside from law enforcement or local government geo-mapping.)
Listening, often you will hear a drastic backing off, of throttle, engine noise, as a plane drifts above, very low and sometimes moving in some lazy arc or circle.
My interpretation is like: "Honey! Can you see me (us)?", as the student flight lesson proceeds.
The lazy throttle down sounds have become the hallmark, of flight lessons, for me. Not that irritating, it just seems obvious: Most other flights seem to be oriented on 'getting somewhere', rather than lingering.
I've often assumed that some flights (lessons) are kids / older students, that made 'honor roll' or some such...
-- I'm just saying...