What are some cute suprising things you can do to make your boyfriend happy and get butterflies in his stomach?

Draw him a sweet picture, write him a song or a poem, buy tickets for a concert of a band that you know he likes or just get something that you know he'd like. Then the most important part is to have him get it in a surprising way. For example, if you send a drawing or poem through the post (maybe in an envelope that doesn't show that it's from you), he will be surprised when the completely random letter is such a sweet gift from you. You could also put your gift in his school bag secretly.