Simplify the following text for a Grade 11 native English-speaking person.
Original: In 1900 Mandelstam entered the prestigious Tenishevsky school , which also counts Vladimir Nabokov and other significant figures of Russian ( and Soviet ) culture among its alumni .
Simplified: In 1900 , Mandelstam entered the prestigious Tenishevsky School . The writer Vladimir Nabokov and other significant figures of Russian and Soviet culture have been among its alumni .