Most service year opportunities are full-time (32+ hours per week), full-year (9-12 month) positions that are intended for individuals after high school, after college, or somewhere in between. Unless you are doing a service year that is directly linked to your education, it’s unlikely you would be able to do a service year while still in school. You can choose to take a year off from your studies to do a service year.
You can inquire with individual organizations if it is possible to work outside of your service year position; however, it is unlikely you would be able to do another full-time job due to the hours commitment.
While the majority of service year opportunities are full-time and full-year, there are a handful that are not. We don’t have a specific filter to search for part-time opportunities, but you can see in a listing what the specific term commitment will be (start and end date). For searching, you can also try keywords such as part-time, half-time, or summer.