Read the passage carefully and choose the correct answer.
Mr Green: Hey, Tom. How's your first week at the new school?
Tom: Well, it's great. But I was a bit nervous at first.
Mr Green: Why were you nervous?
Tom: The teachers are all new to me, most of my classmates are new too.
Mr Green: Are they friendly to you?
Tom: Ah, yeah. They are all nice to me.
Mr Green: What subjects did you have today?
Tom: Well, we had maths, geography and computer studies, my favourite subject.
Mr Green: Oh, good. So everything is going well at school?
Tom: Right. I had a good first day. And ... Dad, can I join the judo club at school ? I like to do judo.
Mr Green: Yeah, OK, if you like. But don't forget to do your homework.
Tom: I won't. Thanks, Dad.
Why was Tom nervous at first?