he has spent years cramming for a variety of tests,
to cram: apiñar, embutir. If you cram things or people into a container or place, los metes dentro, aunque apenas hay espacio suficiente para ellos. || If you are cramming for an examination, estás estudiando/aprendiendo todo lo posible en poco tiempo justo antes del examen
Cram school: A cram school (colloquially: crammer, test prep, tuition center, or exam factory) is a specialized school that trains its students to achieve particular goals, most commonly to pass the entrance examinations of high schools or universities. (Wikipedia).