For one of my short answer essays, I have to write about an activity I enjoy doing. Could I choose my activity to be a part-time job?
My suggestion would be to go for something more unique. While that topic will work it won’t help set you apart.
Caltech (a very prestigious school) boasts having kids that juggle cigar boxes, lip-sync to Taylor Swift, chases runaway chickens ect. Things like that make you interesting to admissions, and allow you to add a human element to your application.
I have also heard it is a good idea to give Admissions people something super memorable so that when they are debating they can be like “I want the guy who has abnormally large feet” etc. I am not sure how credible that is.
Remember they should already be able to tell how smart and hardworking you are by your transcript, awards, and activities. Essays are where you make it absolutely clear that you are not a robot but instead a multi-dimensional character that will bring life to their school culture.
Good luck!
I think your activity should be what you can write the best and most genuinely about. Don’t make up a weird activity to impress them - if you love your job then write about that.