quick study

a quick study -- схватывать все на лету; легко даваться (об учебе); толковый, светлая голова

Meaning: someone who learns things quickly; someone who is apt to catch on to things fairly quickly and easily

Example: "The choreography is pretty complicated, but she's a quick study."
'Someone who is apt to catch on to things fairly quickly and easily' is also [quick on the uptake]