Yes, STUDENT is a Scrabble word!

Letter values in Scrabble US: S 1, T 1, U 1, D 2, E 1, N 1, T 1.

Is it a valid word?

STUDENT is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a learner who is enrolled in an educational institution
a learned person (especially in the humanities); someone who by long study has gained mastery in one or more disciplines

Also: scholarly person.

Not playable in Scrabble US: EDUCATEE.