I will guess that the idea of college admissions is driving her a little bit. Some people, not just students, see all these opportunities and want to take advantage of them. This problem will only get worse when she sees what is available in college. So, she needs to learn to manage herself now before it really gets out of control.
Point out to her that ECs for college admission are a game of quality over quantity. Taking an active role and accomplishing something is viewed much better than just being a “joiner” and not participating as much as she should.
Taking the time to study and get the best grades she can is also important for college applications as well as feeling good about yourself.