Shelly was able to remember the names of three new class members for only a minute or two after they had been introduced to her. during this time their names were stored in her memory.

During this time their names were stored in her short-term memory.

Explanation:

"Short-term memory acts as a kind of “scratch-pad” for temporary recall of the information which is being processed at any point in time, and has been referred to as “the brain’s Post-it note”. It can be thought of as the ability to remember and process information at the same time. It holds a small amount of information (typically around 7 items or even less) in mind in an active, readily-available state for a short period of time (typically from 10 to 15 seconds, or sometimes up to a minute)."

Reference: The Human Memory. “Short-Term Memory & Working Memory: Definition, Duration & Capacity.” The Human Memory, 8 Oct. 2019, human-memory.net/short-term-working-memory/.