I'm going back to in person teaching, so I need enough masks so I can switch them out if needed during the day. I have 5 that I find comfortable,and have filters, and 4 lighter ones that I can wear outside for a bit, or running into stores. I'm wondering if 5 is enough for school? How many do you have? P.S. I just saw the masks I liked the best for $7.88 for 4- free shipping. I just paid $12.00 for 4, so I couldn't resist!