Let's follow the case of a family preparing to move to Arlington Heights step by step. They found a property on a listing site that showed a score of 10 for the assigned elementary school. Since 10 is the highest score, they thought there was no need to look further and proceeded with the contract. However, just before signing the contract, they checked again and found that the address was divided between District 25, which oversees elementary and middle schools, and District 214, which oversees high schools. They had assumed that the high school would have the same score just by looking at the elementary school score.

At this point, there's something important to note. In many areas of the U.S., including Illinois, elementary and secondary school districts often operate separately from high school districts. The score of 10 that this family saw was for an elementary school in District 25, while the actual assigned high school was John Hersey High School in District 214. Fortunately, this school also confirmed a GreatSchools score of 10, but if they had been assigned to a different high school, the situation could have been different.

Within District 25, Ivy Hill Elementary School and Patton Elementary School both received scores of 10, while other schools scored between 8 and 9. District 214 has 11,911 students and a student-to-teacher ratio of 15 to 1 (according to GreatSchools and Niche). In areas where elementary and high school districts are separate, it's essential to check both scores to get an accurate picture. Making a decision based on just one score means you're only working with half the information. Many townships in the Chicago suburbs have this dual structure, so this is not a unique situation to Arlington Heights.

The order of authority for this family is as follows. First, they need to confirm which elementary/middle school district and which high school district the address belongs to. Next, they should individually check the GreatSchools scores of the schools under each district. Then, they should look at the score trends over the past 3 to 5 years. Finally, they should check the student-to-teacher ratio and reviews. Since scores are a composite of test results, college readiness, academic growth, and equity, it's better to follow this order rather than making a judgment based on just one item to reduce mistakes.

If a family is moving to Arlington Heights from another state, they also need to factor in property taxes. Illinois has relatively high property tax rates compared to other states, and the higher the school scores, the greater the property tax burden tends to be. If they budget based on the property tax rates from their previous state, there could be a significant difference in actual monthly expenses. By calculating the estimated property tax for the address of interest on the Cook County Assessor's website, they can compare school scores and tax burdens together.

This family was able to confirm the separation of school districts just before signing the contract because they called the school district office themselves, not because of their real estate agent. The scores on the listing site are just reference materials and are not documents that legally confirm the assigned school. It's safer to go through the process of directly checking the address with the school district office or county education department before signing the contract. This process may feel cumbersome, but a quick 5-minute confirmation call can prevent confusion later on.

To summarize the items to check:

• Whether the elementary/middle school district and high school district are separate
• Individual verification of GreatSchools scores for each school under the districts
• Score trends over the past 3 to 5 years
• Student-to-teacher ratio
• Actual assigned school based on the address (check with the school district office)

In areas where districts are divided, it's difficult to make a judgment based on just one score. This article is not investment or legal advice, and it's recommended to verify again with the relevant school district office and real estate professionals before making any contracts.