Most berlin museums offer student pricing but tourists don't know international student ids work. Museum island is €14 regular, €7 with student id. Same for jewish museum, ddr museum, etc

Some places like topography of terror are already free but paid special exhibitions often have student rates. Always ask even if not posted - worst case they say no

If you're under 25 some places give youth discounts without student status. Berlin is surprisingly student-friendly for culture stuff