Elementary school kids, a lucky charm they can take along

Elementary school kids feel lonely and stressed out sometimes when they have a test, so they would like it if Mom or Dad would think about them and they are well prepared for tests. Mom and Dad came up with an idea to give the child a lucky charm which they will always have with them. This way they feel thought of and less intimidated by tests or other stuff in school.
I used a sticker, one which my child also liked a lot, stuck it on a piece of paper and also wrote something on it like "I can do this", "I am fit", or "I am well prepared".
This piece of paper which should not be too big, is then laminated so it stays nice for a long time. My child really loved this lucky charm and feels great about it whatever situation they are faced with in school.