be beyond (one's) ken

To be advanced beyond one's ability to understand or make sense of the subject matter or task at hand. The stuff they're teaching in this advanced math class is beyond my ken.

Common Names:

Name	Pronounced	Usage
Ennius	-	Ancient Roman
Nikolay	nee-kah-LIE (Russian)	Russian, Bulgarian
Vartouhi	-	Armenian
Ada	AY-də (English), AH-dah (Polish, Finnish)	English, German, Polish, Hungarian, Italian, Finnish
Lizzie	LIZ-ee	English
Avksentiy	-	Russian