Funny thing

Today the day end quite fast and I thought it was cool. Didn't get any scolding. My manager suddenly told me that I should take the spelling homework for her every monday morning together with the notebook. She said I forgot. But I didn't forget, because she didn't tell me before. She always remember to take it with her when she come. But today don't know what went wrong. But anyway I'm the assistant, when she forget I should remember for her. I learned one thing about her. She will forget things and I just have to go along with her. If not what can I do?