Urban Garden Tips

Hey everyone,
This school I help at in Providence, RI received $100 to plant a flower/vegetable garden on a rectangular piece of grass (we’re gonna dig it up).

Unfortunately, I know little about gardening, better yet in urban cities. Here’s specifically what I’m looking to find out:

* What should I do to get started? Do I need to dig 2 ft and start with fresh soil? Do I use some kind of tray/planter?

* What vegetables/flowers grow best & are most durable? (I was told to use perennials *not* annuals).

* What kind of fence should I use to protect it?

* How do I keep it coming back each year? What maintenance is involved?

I know those are a lot of questions, but I’m completely clueless. Any tips/suggestions would be greatly appreciated! Thanks so much in advance

PS: Some plants I was considering:
tulips, daffodills, tomatoes, eggplant, basil…