No one has a bad memory or good memory. It all depends on how we train our mind. We teach techniques which help a child to remember, retain and recall, short term memory, long term memory, photographic memory, Memory games, mental gymnast and so on.
Memory is related to your brain. It is one of the brain functions. Some people are good at memory and some people are not.

Stimulates long term & short-term memory
Help to score good marks in academics.
Activates the brain.