Every true professional works within certain ethical guidelines and this is certainly true for grant writers. Even if you work at it part time, and teach full time, you’ll be putting on a tighter ethical hat when you enter your grant world. You are dealing with and managing money. The temptations to abuse the trust you’ve been given are there, but not if you’ve set up your office and standards to be strictly ethical in the first place.
One of the reasons it’s so difficult to buy things for your classroom through regular school district channels, is the layers of oversight that are built in to the purchasing process. It’s driven by state law and experience gained from lessons learned. Be grateful, it will release you to pay firm attention to the task at hand, raising money for your kids. Leave the purchasing process to the purchasing professionals.