9 truths and a lie

Can you guess which one of the following is not true?

1. Robin and I each wore our new orange teacher shirts to school today.

2. Thanks to lots of singing in classes today and lots of out-loud reading yesterday, my voice hurts.

3. Tomorrow is Robin's birthday.

4. Tomorrow is my Grandpa Crandall's birthday.

5. I kinda forgot about tomorrow being Robin's birthday until I got a reminder about it from Myspace.

6. Tonight, I am taking Robin out for her birthday.

7. I made an eighth grade student cry today. (It was the second eighth grader I've made cry this year.)

8. When asked on a quiz today to give advice to a friend who is leaving her home for a week, one student wrote: Don't forget to eat the dog.

9. After school today, Robin and I practiced music and then played volleyball with some of the other teachers.

10. During the volleyball game, I cut myself with my own fingernail.