Elementary You Say

[skabooya]

Finally got a job teaching grade 6/7 split. Its gonna be hard after being on mat leave and then there being no jobs for another semester after that. But anyway, I got one anyway and am so excited.
I want to put a simple SW tank in the classroom. It needs to be small enough for me to carry back home a the end of the year. Simple enough so that its VERY easy to maintain, tear down and put back up. Interesting inhabitants. I find kids dont think fish to be super interesting but crabs, shrimp, worms .... basically creepy crawlies are fun. lol

Anyways this is what I am thinking.
4 gal glass tank.
Some light thing. Dunno what yet. It may even be sun lit. No super spending here if any.
Either 1 piece of LR or 1 large piece of Dead rock.
no corals unless its a hitch hiker. Even then as cool as it would be I dont think it would survive because of the low light and having to move around.
HOB filter provides flow and some filtration
inhabitants: hermit crabs 2 max, feather duster worms... anything else? Some red macro that I already have will get thrown in anyway. Shrimp are expen$ive. I would love some snails but they probably wont make it with the crabs.
OH and some sand.

Any inputs or suggestions. I want to have this planned out before actually putting it together.