Prep Middle - Mastery Charter School

Are you looking for grades 9-12?


Prep Middle is now accepting applications for the 2024-2025 school year. Please follow the steps below to apply online.

  • Visit Apply Philly Charter
  • Log in or create an account
  • Fill out your family profile and add your child as a student
  • Click on the Apply for September 2024 button
  • Select Mastery Charter Gratz Prep Middle School as the school to which you would like to apply
  • Submit your application

Please note: If you are looking for a seat for your child for the current school year (2023-2024), you can still apply online today using Apply Philly Charter. Just click on the “Apply for Current Year” button to start your application once you’ve logged in.

Have questions about our school or need help navigating the process? Complete and submit this form, and a Mastery enrollment specialist will reach out to answer your questions and help you apply.

Your Neighborhood School in North Philadelphia

Welcome to Prep Middle! We’re a small neighborhood school in North Philadelphia serving 275 students in grades 7-8.

Our rigorous academics ensure students are fully prepared for high school and our sports & extracurricular programs allow students to lead and succeed outside of the classroom. We are in the top 10 schools in Pennsylvania for reading growth.

Students enjoy a strong sense of community and belonging in a safe environment, supported by caring and committed teachers.

At Prep Middle, all students learn and thrive. With love and high expectations, we help them find their own paths to success.

Stop by and visit us any time!





Our School

Our academically rigorous program prepares all students for success after graduation.

  • High school prep program tailored to the individual needs of students at all levels in a small setting
  • 2 math & 2 reading classes, with a focus on writing
  • Graduates admitted to the top high schools in the city
  • Robust extrucurricular programming: including photography, soccer club, football, basketball, volleyball, track & field, flag football, and anime


  • Special Education Programming
    • We provide comprehensive special education programming to meet the individualized needs of each child, including:
      • Individualized Education Plans
      • Academic Interventions
      • Low Incidence Programs  (Autistic Support, Multiple Disabilities, Life Skills)
      • Emotional Support
      • English as a Second Language (ESL)
      • Psychological and Social Services


Prep Middle students have tons of sports, clubs and extracurricular activities to choose from, including:

  • Soccer
  • Flag Football
  • Basketball
  • Volleyball
  • Drum Line
  • Anime Club
  • Photography and Film Club
  • Poetry Slam Team
  • Art Club
  • Cooking Club


Admission to Prep Middle School is first come, first served to students living in the Gratz High School attendance zone and students currently attending:  

  • Bethune 
  • Cleveland  
  • Clymer  
  • Duckrey  
  • Kenderton  
  • Steel  

Students from schools not listed above and outside the Gratz attendance zone may also apply for the lottery, however they can only enroll if seats are available.  

In the News

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Our Team

Kate McNulty, Principal

Kate McNulty is the proud principal of Prep Middle School. Ms. McNulty returns to the Gratz community after most recently serving as the Senior Director of School Culture on the Equity and Student Development Teams at the NST for the last three years.

Over the last 14 years, Ms. McNulty has served as an teacher, school leader and central office leader. She began her career in the School District of Philadelphia as a middle school math teacher before joining Mastery Schools at Simon Gratz High School. At Gratz High School Ms. McNulty taught social-emotional learning (SEL) and Pre-Algebra to 9th graders and served as the Assistant Principal of School Culture.


Ms. McNulty earned her Master’s Degree in Education from the University of Pennsylvania and a Master’s of Business Administration and Bachelor of Science degree in Psychology  from Thomas Jefferson University (Philadelphia University).


Some of Ms. McNulty’s goals include continuing and growing the rich academic and extracurricular culture at Prep Middle as well as working with students and families to create even more opportunities both inside and outside of the school community. Outside of school, Ms. McNulty enjoys participating in and watching sports and spending time with her family and friends.

Our staff is available to support you and your child throughout their school experience. We are available to meet with families and answer questions via the email addresses listed here.


"There's a charter school called Mastery in Philadelphia. And in just two years, three of the schools that Mastery has taken over have seen reading and math levels nearly double - in some cases, triple...Now, if a school like Mastery can do it, every troubled school can do it."
-President Barack Obama