I love to shop the dollar tree for school stuff. They always have neat things that are only $1. Also, shop garage sales, goodwill, & salvation army stores. YOu know what they say about one man's trash being another's treasure.
Good Luck & Congrats on entering the best profession there is.
the dollar store has lots of stuff. It is hit and miss though. I would caution you to not buy tons of things yet until you have a class. Your needs will change from grade to grade.
Also Target has things in their dollar bins expecially at the beginning of the school year. I got a cute grader slide. That you will need for any grade. Just ask yourself...can I use this in kindergarten AND 6th grade? Then you will know if you should buy it or not.
Lay in a supply of: ziptop bags in all sizes, paper lunch bags, paper plates in both sizes, foil, plastic wrap, extra file folders, glue sticks, white out, both sizes of envelopes, breath mints, and Aleve.
Congrats and good luck!