Several times I switched classes, grades, schools, only to discover a bare room, or materials that could easily be called junk. The first conversation I had with a principal said, "Creative teachers could make do with anything."
There was a time our school system had mini- grants in September. It rewarded creative teaching that went above and beyond the curriculum. I would pick a subject, and then order $500.00 worth of supplies around that topic. Next, I would follow the application questions making sure my materials answered the questions. Presto! I received every grant I applied for. Fun experiments, and activities that would think outside the box. After a few years the system wanted to cut costs and they eliminated the mini-grants. Too bad, although I continued to use my materials for years.
This is the best advice I can give a teacher. Do not spend any personal money on school supplies. It can get addictive, and that is certainly not what you want. Every time you see something you want to buy, list it on your phone under notes, along with its cost. Then total your sum and put that money into your 403B, (Your retirement account).
Scholastic books are addictive. As soon as you get those magazine ads, throw them in the trash without looking at them. Keep a list of the books you would like for your classroom and two days before school ends in June, when the reading teacher tells you she needs to know what you would like for next year, give her a copy of your list. Make sure you write objectives to justify your purchases.