Is there a age limit to become a CFI? I’m a new PPL and I would love to become a CFI in the next 2 years (or so). My objective would be to transfer what I know (and will have learned) to aspiring pilots. I’m older, though (just about to turn 60). Put it bluntly: am I too old? I know that we can’t talk about people being too old for almost anything these days, but I really would like to know if anyone (e.g. a flight school) would hire an instructor who not only brings rather thin experience (300-400 hrs by then) but combines it with rather ‘advanced age’. The benefit for a school would be that this would be my ‘forever-job’ (first, part-time and then full-time after I retire from my ‘day-job’ in a few years), not a stepping stone to an airline career. Please, feel free to tell me what you really think…
A flight school won't care too much about your age if you have the required medical.  And mentally, your age is an overall plus since a flight school would generally prefer a mature individual in it because they want to teach to a 25 year old who's just building time.  The turnover with flight schools is quite high so the prospect of getting say at least 5 years out of you is another plus because they may be only getting 2-3 years out of younger instructors in the current environment (often they are basically only hanging on to get to 1500 hours under the "Colgan Rule" craziness).

I would say that that if your health is fine and shows no signs of problems over the next 5 years at least, you should definitely go for it.  You might even get a school to commit to hiring you, or at least giving you a shot (it's going to come down to how good a teacher you are), if you train with them.

With the general shortage of bodies all through the system, I don't see any downside if you really keen on doing it.  If you gain a reputation as a good teacher students will gravitate to you over the youngsters.