To use an IT analogy, those are MVPs - minimally-viable aircraft.
Most ultralights don't have closed wings, so there's no structure as the public would understand it. So spend $20,000 and get the best ultralight available if you go this route. I wouldn't take friends or family up in an ultralight since they can't evaluate the risks.
Beyond that, LSA aircraft only require a drivers licence, and look like real airplanes. But no night or IFR operations are allowed. These were supposed to be cheap, but are priced like real airplanes since buyers demand glass panels, etc.
It’s like 90% of the flight training content of the Private. For some reason, the FAA thought it would also be good to drop the minimum time from 40 hours to 20 hours when they made Sport Pilot. This especially makes no sense because almost no one finishes the Private in 40.
So AOPA, EAA and the LSA manufacturers get old guys hyped on getting a pilot’s license with only 20 hours in the cockpit plus 0 time in the doctor’s office, and they walk into my flight school. Then we have to a conversation about realistic training expectations and how if there’s “no way in hell” you’d get a medical, maybe we should consider if being pilot-in-command of an airplane is really for you.
The FAA medical exam was expanded to evaluate people for neck size/apnea. So for most overweight Americans, seeking a PPL or Sport, they're better off going LSA to avoid paying for a sleep study and risking a medical rejection, which will cause life-long FAA problems.
I would suggest that instructors should figure out if a student confuses flying an airplane with operating a boat. One is pure work, and the other is perceived as pure relaxation.
(Boating used to be equated with drinking beer, but I think it's illegal to operate a boat now while drinking, after some horrific accidents.)
So you (or your students) could check their BMI and get in shape before the exam, or just go the LSA route.
faa.gov: Decision Considerations Disease Protocols Obstructive Sleep Apnea (OSA)
https://www.faa.gov/about/office_org/headquarters_offices/av...
Somebody's personal story:
https://insidethecockpit.com/airline-pilots-with-sleep-apnea