Study or Read

What's correct or grammatical?
1. I read in grade III.
2. I study in grade III.
3. I'm in grade III.

Thanks a million!
Star Pupil

[David L.]

3 is correct

[Dawood Usmani]

Originally Posted by David L.

3 is correct

So the rest are grammatically incorrect? Can't we say I read in grade III?
Best regards!
Dawood

[David L.]

I think you mean, "I read at a grade III level."