From Wiktionary, the free dictionary
Sechs f (genitive Sechs, plural Sechsen)
- six
- A failing grade in a class or course at school. The grades range from 1 (best) to 6 (worst).
Declension of Sechs [feminine]
- “Sechs” in Digitales Wörterbuch der deutschen Sprache
- “Sechs” in Uni Leipzig: Wortschatz-Lexikon
- “Sechs” in Duden online