The top reported proficiency rate is 49% in English language arts. The lowest is 26% in Math.
Original Research by School Decision on Costello School
Costello School is a small elementary school serving children from preschool through fifth grade in Lyons, a working-class village about ten miles southwest of Chicago. The school enrolls around two hundred students, with a student body that is predominantly Hispanic, alongside smaller populations of white, Black, and Asian students. The school is part of Lyons School District 103, which covers several nearby communities.
On state assessments, Costello's results show uneven performance across grades and subjects. In English language arts, the school's proficiency rates range from below to above the midpoint: third grade shows stronger performance while fourth grade dips noticeably lower. Fifth grade returns to a level around the midpoint. In mathematics, the picture is considerably softer. Third grade achieves the lowest reach of the school's math cohort, fourth grade falls sharply, and fifth grade math proficiency is very low. In the one science assessment administered at the school, fifth grade science also runs below the midpoint. Across tested subjects and grades, the school's overall proficiency index sits below the midpoint when compared to districts across Cook County. The Illinois state assessments underwent scoring adjustments in the 2024-25 school year, so comparisons to prior years are not yet available.
The district has adopted a new K-5 math curriculum called ORIGO Stepping Stones. The shift is intended to be supported by parent resources, including a dedicated portal and newsletters explaining the instructional strategies families will see their children working with. A parent weighing Costello will want to understand how this curriculum aligns with their own views on math pedagogy and their readiness to engage with a new approach.
Lyons itself is a mixed-use village built around a manufacturing and logistics heritage. Housing is mostly mid-20th-century single-family homes, with a median home value in the range of what would be considered affordable for the Chicago region and modest rental rates. The village's civic life is distributed along commercial corridors rather than concentrated in a single downtown; the library and municipal offices are a few blocks from one another in the central village. Schools and parks sit within walking distance of residential blocks. Public transit is available via several Pace bus routes, though the nearest Metra commuter rail is in adjacent communities.
The district has experienced a steady enrollment decline over multiple years, a trend that can carry implications for per-pupil funding and long-term staffing. In addition, the district is defending an ongoing federal discrimination lawsuit filed by a former superintendent and assistant superintendent, with a judge denying the district's motion to dismiss in early 2024. This remains unresolved litigation that, while not directly affecting classroom instruction, represents an active governance and budgetary matter families may wish to be aware of.
For families considering Costello, the school offers a neighborhood setting within an affordable community, but state assessment results suggest the school is navigating meaningful academic challenges, particularly in mathematics. Parents looking for strong early-grade literacy instruction or reasoning-based math support may want to investigate further, either directly with the school or by exploring other schools in the district or nearby.
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