Yes, RESINS is a Scrabble word!

Letter values in Scrabble US: R 1, E 1, S 1, I 1, N 1, S 1.

Is it a valid word?

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

any of a class of solid or semisolid viscous substances obtained either as exudations from certain plants or prepared by polymerization of simple molecules