my 2yr 8mon son doesn't pay attention in class or answer teacher questions unless in 1-to-1 conversation although he speaks well compared to his age.
My son is very energetic and can play all day but he spends few min playing in one toy then goes to another. He does not accept to sit on chair at all and always jumping or wandering around the house. In preschool, he accepts to sit down but does not pay attention or more precisely does not look at teacher but looks around. He does not answer the teacher questions in front of the class unless she brings him into one to one conversation. On the other hand, at home he reflects very well what he learns at school, meaning although he is not looking at the teacher but learning very well. To mention that his language is even better compared to his two girl cousins of same age, is not shy at all as he speaks to any one he meets or to family. At home, I give him a lot of dedication, attention, care, play with him and teach him a lot. His teacher is not able till now to know the reason why he is like this at school and I feel that she needs my help and I do not know what to do, because I see him a very sociable & smart boy while it is not the case in school. in my opinion, he has no anxiety disorder or hyperactivity problems but what, I do not know
It sounds like your son is a very typical, normal 2 almost 3 year old. It also sounds like your are a very dedicated parent and teaching him what he needs to know. By you giving him attention and time to play, you are allowing him to grow and develop just as he should be.
I want to stay up on my soapbox very long... Kids need to be kids. Perschool should be a time to play, socialize, sing, dance, explore and just have fun. It is my personal belief that often time kids are pushed to read, write, sit still, answer question in complete sentence way too early.
Developmentally, your son is at the stage where he likes to play with other around him, but not necessary with them. He will play with one toy, see another and go to that one instead. If he doesn't see the toy, he will forget about it and find something else. He there will find something that just fascinates him like a bug and then watch it for a long time. This is all normal. Education.com has some great resources on the development stages and the ages they are associated with. Be sure to check them out.
One thing that you can do if you aren't already doing that will make the most impact on his education and learning is to read to him daily. Try to read three books a day - one he chooses, one you choose and an old favorite. Research has found that this has many benefits. I suggest reading Mem Fox's book, Reading Magic. She explains to parents how to read aloud and the gift you can give you son at the young age.
So take a deep breath and enjoy your son. You're doing fine!