beyond (one's) ken

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
Dietrich	DEET-rikh	German
Shakuntala	-	Hinduism, Indian, Hindi, Marathi
Reynold	REN-əld	English
Wenda	WEN-də	English (Rare)
Nicanor	-	Ancient Greek (Latinized)
Brewster	['bru:stə]