What Makes a Good School? 5 Factors That Actually Matter
Published April 2, 2026 · Data Analysis
Parents often judge schools by reputation, neighborhood, or how much they spend per student. None of these reliably predict student outcomes. After analyzing 88,000+ schools, here are the five factors that actually separate good schools from mediocre ones.
1. Academic Proficiency Rate
The percentage of students meeting or exceeding grade-level proficiency in reading and math is the most direct measure of academic quality. It answers the fundamental question: are students learning what they need to learn? This factor accounts for 35% of the DataScore because it represents the core mission of any school.
The national average proficiency rate varies by state due to different standards, but within a state, proficiency rates are highly comparable. Top-performing schools consistently achieve proficiency rates above 70%, while struggling schools often fall below 30%.
2. Growth Trend Over Time
A school's trajectory matters as much as its current position. We measure the 3-year trend in proficiency rates to identify schools that are improving versus declining. This factor is weighted 30% because a school getting better each year is likely a better choice than one that peaked three years ago and is now sliding.
The most improved schools in America show growth trends of +15 to +30 points over three years — transformative improvement that fundamentally changes student outcomes.
3. Graduation Rate (High Schools)
For high schools, graduating students is the minimum standard of success. A school that teaches well but loses a quarter of its students before they finish is failing a significant portion of its population. Graduation rate accounts for 20% of the DataScore for high schools. The top schools by graduation rate achieve 98-100%.
4. Student-Teacher Ratio
While not directly part of the DataScore formula, student-teacher ratio is strongly correlated with outcomes, especially in elementary grades. Schools with ratios below 15:1 tend to have higher proficiency rates and stronger growth. See our analysis of what constitutes a good student-teacher ratio.
5. Resource Access
The resource access score (15% of DataScore) measures whether students have access to the physical and instructional resources they need. This includes library access, technology, counselors, and specialized instructors. It's weighted lowest because resources are an input, not an outcome — but schools without basic resources face significant headwinds.
What Doesn't Matter as Much as You Think
- Per-pupil spending — Above a baseline, more money shows diminishing returns
- School size — Both small and large schools can be excellent
- Age of facilities — Building quality has minimal correlation with outcomes
- Neighborhood home prices — Wealth correlates with scores but not with growth
Frequently Asked Questions
What is the most important sign of a good school?
Consistent 3-year growth in academic proficiency is the strongest signal. A school where students are improving year over year — regardless of starting point — demonstrates effective teaching and leadership. This is why growth trend is weighted 30% of the DataScore.
Does more funding make a school better?
Not necessarily. Research shows that above a baseline threshold, additional per-pupil spending has diminishing returns. How money is spent matters more than how much is spent. Some of the highest-scoring schools in the DataScore system operate with below-average funding.
Do school ratings capture everything?
No rating system captures everything. The DataScore measures academic outcomes — proficiency, growth, graduation rates. It does not measure arts programs, social-emotional learning, school safety, or student happiness. These intangible factors are important but require in-person evaluation.