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
Taika	-	Finnish (Rare)
Ljupcho	-	Macedonian
Paquita	-	Spanish
Lycurgus	-	Greek Mythology (Latinized), Ancient Greek (Latinized)
Gaenor	GAY-nawr	Welsh
Herman	HUR-mən (English), HER-mahn (Dutch)	English, Dutch, Swedish, Norwegian, Danish, Slovene, Ancient Germanic