There’s no one-size-fits-all answer here. This depends on how you manage your time, and how many extracurricular activities you can handle without it affecting your sleep, stress, or school work. The thing to keep in mind here is that your extracurricular activities should be achievable without being overwhelming. If, for example, your extracurriculars cause you to fall behind with school, then that’s probably already too many of them. On the other hand, if you feel like you have too much free time that you don’t know how to fill up, then taking up a couple of more activities probably wouldn’t hurt.  Typically, students say three to four activities are achievable, without being overwhelming.