What to keep in my purse?

i am 16. I have a huge tote bag that i want to start carrying around. I keep my cell phone in my pocket so if i ever lost my purse my 300 dollar phone with all my info wouldn't be gone as well. I have a comb, some hair ties, a mirror, crayons, my wallet which i only keep 25 dollars at a time in, lotion, deodorant, a mini chess board, gum, chap stick and pads in. I don't wanna keep hundreds of dollars worth of stuff in it. I don't want all of my nice stuff to be gone cause my purse went missing. So don't tell me my ipod, or handheld stuff. Ideas that would be helpful for everyday life. I am with dogs a large part of the day. Would it be weird to keep dog treats in it? What do you keep in your purse?