Optional 3rd grade work

In the class I subbed in today one student decided that everything I asked him to do was optional and he decided to not do anything. After going through the card turning and the "NO" he went to sit in the hall on a break, but kept making faces and gestures in the doorway. After lunch and gym he decided that instead of math he would sing loudly at his seat. After a few times of asking him to stop, I marched him down to the office getting more upset every minute. I'm sure I sounded and looked exasperated when I opened the office door and told them I did not want him back. They just smiled and nodded knowingly. Some days as a sub are great and some are not, this was the hardest day I've had so far this year. I've been very lucky. I love specials(gym, special ed., art, music, etc.), preschool and kindergarten. Only problem is I usually get sick a few days after kindergarten, its a germ factory there.