Simplify the following text for a Grade 5 native English-speaking person.
Original: Lefebvre entered the Ã cole nationale supÃ rieure des Beaux-Arts in 1852 and was a pupil of LÃ on Cogniet .
Simplified: Lefebvre went to the Ã cole nationale supÃ rieure des Beaux-Arts in 1852 . He was a pupil of LÃ on Cogniet .