Best High Schools in Zip Code 03303

ZIP code 03303 has two public high schools serving grades 9–12: Merrimack Valley High School and CSI Charter School, offering families a choice between a larger district high school and a very small charter school. Merrimack Valley High School enrolls 744 students in the Merrimack Valley School District, while CSI Charter School enrolls just 34 students.

Based on the current information available, Merrimack Valley High School has the stronger overall profile. Its 2024–25 graduation rate was 91.2%, above New Hampshire’s 87.0%, and its dropout rate was 2.0%, slightly below the state rate. Reading is the school’s strongest academic area: 57% of students reached proficiency in the 2025–26 NH SAS, close to the state’s 55% and above the district’s 53%. Mathematics and science are more significant concerns, with proficiency rates of 19% and 27%, respectively, compared with 44% and 38% statewide. Test results declined from the prior year in all three subjects, and the school’s ranking fell from the 70th to the 29th percentile.

CSI Charter School has a much smaller setting, but its reported completion outcomes are weaker. Its graduation rate was 53.8% and its dropout rate was 3.8% in 2024–25. Because the school has only 34 students, individual students can substantially affect percentages, so families should ask about cohort size, transfers, credit completion, and attendance. CSI has no current test-score results in the supplied data, and its only ranking record is from 2009–10, making current academic comparisons impossible. Families prioritizing established performance data may find Merrimack Valley High School easier to evaluate, while those considering CSI should seek updated information directly from the school.