I once spoke with a newlywed couple looking for their first home in Pasadena. They saw a school score of 8 on a listing page and thought it indicated a good school, but they were unsure of what that score was based on. They asked if a score of 8 simply meant good test scores or if other factors were considered.

The GreatSchools score is not determined by test scores alone. It takes into account test scores, academic progress, equity, and for high schools, college readiness. The calculation method gives a weight of 0.45 to the higher of the test score rating or academic progress rating, while distributing 0.27 to each of the other categories, resulting in a two-step weighted average (source: GreatSchools Ratings Methodology Report). Even if test scores are high, a low rating in growth or equity can lead to a lower overall score.

Looking at a few elementary schools in Pasadena reveals this difference. Field Elementary and Willard Elementary both have scores of 8. In contrast, Madison Elementary, also in the Pasadena Unified School District, has a score of 2 (source: greatschools.org). Nearby Arroyo Vista Elementary in South Pasadena has a score of 9 (source: greatschools.org). It's also important to note that Pasadena and South Pasadena are separate school districts.

The college readiness category also needs to be considered. This category is calculated by averaging graduation rates and college entrance exam (SAT, ACT) scores, each contributing 50 percent (source: GreatSchools Ratings Methodology Report). If you are considering high school assignments, it is helpful to look at this category separately.

It's also beneficial to examine the academic progress category. This category shows how much the same group of students improves each year, and there are schools where the growth rating is high even if the test score rating is low (source: GreatSchools Ratings Methodology Report). If you are curious about the direction of progress rather than just the current numbers, be sure to check this category separately.

Looking at the equity category is also advisable. This category shows how well students from disadvantaged backgrounds, including low-income students, perform (source: GreatSchools Ratings Methodology Report). If there is a significant gap between test scores and equity scores at a school, it may indicate a structure that favors a specific group of students. The Pasadena Unified School District website offers a search function where you can enter your address to find out your assigned school. If the school information differs from what you see on real estate sites, it's safer to rely on this official search result.

When actually choosing a home, I recommend checking in this order:

• Look at the detailed components that make up the scores (test scores, growth, equity).
• Reconfirm which school district and boundary the property address falls under.
• Review the trends in ratings over the past few years.
• Keep in mind that the student-to-teacher ratio may differ from actual class sizes.

For families moving to Pasadena from other states, it's worth noting that the proportion of private schools varies by area. In some neighborhoods, even if public school scores are somewhat low, there may be plenty of private school options, making the perceived quality of the school district feel different. Before judging an area solely based on public scores, it's helpful to also look at what choices families in that neighborhood are making.

In areas like Pasadena, where school district boundaries are closely packed, understanding the composition of the scores is often more beneficial than focusing on a single number. This article is not investment or legal advice, and it is advisable to check the latest assignment information with a professional before making any contracts.