I do purchasing for a middle school, and our science teacher does a rocket unit with his 8th graders. We typically order through Amazon with a business account with discounts. By the time I went to order from when the purchase order was filled out, the price had skyrocketed. I tried this site, but they were out. I was able to sign up to receive an email when they were back in stock (which happened quickly). I placed my order then sent an email to customer service inquiring about tax exempt status. I received a reply quickly, and they told me about a teachers' account. They signed me up for it and refunded the sales tax. Smooth process from start to finish. Thank you!