I agree with Ian - if it's a registered company then you can list it (I can't comment on the tax side but I assume that you should at least have filled in a return, even if it ultimately wasn't subject to tax if the profits were too small). If not then I'd list it in interests. 

If this was a registered company, you should state it. Otherwise, put it as a hobby / personal venture. 

In general, you won't have problems by stating the truth.

Hello,

I would probably list something like this as a side-hustle / self-employment, and make it very clear what the nature of the operations were. I.e. you did tutoring, but more in your own capacity rather than for some large corporate entity.

Hi there,

From a legal perspective I am a bit concerned…no business is tax-exempt (at least from my understanding of US tax law). Double check this one.

I think you can include it, but be careful how you list it. You can't claim that it's a company if you're just tutoring people, mowing lawns etc. Unless you have a real website and a registered business, make sure to list it more as a hobby/side job.