I think they both can have the prepositions.
Not sure though...
1. I am in the first grade in London Middle School.
1-2. I am in the first grade at London Middle School.
(Are both prepositions correct?)
2. How many hours does Bora study in school?
2-2. How many hours does Bora study at school?
(Which preposition do we have to use, 'at' or 'in'?)
2 answers
Yes, Anya is correct. Either preposition can be used in these sentences.