Hey, welcome to the boards!

Before I answer ANY of your questions, I'm advising you to NOT deal in school. When I was in high school people got busted all the time for doing it.. If you want to deal, fine.. but don't do it in school. Be smart about it.

I keep my weed in a mason jar. You know, those large glass jars w/ a sealed lid that your grandma puts canned beans in and stuff? Hell, even a glass jelly jar would do. Weed in just a plastic baggie will eventually dry out and really dry weed burns too fast and is harsh (for me, anyways). A sealed container is best, even a Ziploc bag is decent. Keep it out of the light and in a cool area.

Finally, there's not a whole lot you can do about the smell. Carry some spray stuff that smells good. Gum for your breath. If you're smoking in your room/house/whatever, and there's a risk of parents, stuff a couple dryer sheets into an empty toilet paper roll. Blow your smoke into that.. works pretty well. Get some incense... that'll cover up most of the smell. Blow it out the window..

Have fun and be safe tokin'! Cheers! :rasta: