Serving 847 students in grades Kindergarten-5, Castlio Elementary School ranks in the top 10% of all schools in Missouri for overall test scores (math proficiency is top 20%, and reading proficiency is top 20%).
The percentage of students achieving proficiency in math is 61% (which is higher than the Missouri state average of 40%). The percentage of students achieving proficiency in reading/language arts is 63% (which is higher than the Missouri state average of 43%).
The student-teacher ratio of 13:1 is higher than the Missouri state level of 12:1.
Minority enrollment is 26% of the student body (majority Asian and Black), which is lower than the Missouri state average of 33% (majority Black).
Quick Facts (26-27)
- Grades: Kindergarten-5
- Enrollment: 847 students
- Student-Teacher Ratio: 13:1
- Minority Enrollment: 26%
- Overall Testing Rank: Top 10% in MO
- Math Proficiency: 61% (Top 20%)
- Reading Proficiency: 63% (Top 10%)
- Science Proficiency: 55-59% (Top 10%)
- Attendance Zone: Castlio Elementary serves the eastern part of Saint Charles, MO, covering an area of approximately 7.6 square miles. Parents can typically expect a drive of 5 to 10 minutes to reach the school, with the furthest edge of the attendance zone located about 4.1 miles away.
- Source: National Center for Education Statistics (NCES), MO Dept. of Education
Top Rankings
Castlio Elementary School ranks among the top 20% of public schools in Missouri for:
Category
Attribute
Overall Rank
Math Proficiency
Reading/Language Arts Proficiency
Science Proficiency
School Overview
Castlio Elementary School's student population of 847 students has grown by 5% over five school years.
The teacher population of 65 teachers has stayed relatively flat over five school years.
Grades Offered
Grades Kindergarten-5
(No virtual instruction)
(No virtual instruction)
Total Students
847 students
Showing 2016–2025. Full 39-year historical data available below ↓
Total Classroom Teachers
65 teachers
Showing 2016–2025. Full 39-year historical data available below ↓
School Calendar
School Rankings
Castlio Elementary School ranks within the top 10% of all 2,076 schools in Missouri (based off of combined math and reading proficiency testing data).
The diversity score of Castlio Elementary School is 0.44, which is less than the diversity score at state average of 0.52. The school's diversity has stayed relatively flat over five school years.
Overall Testing Rank
#169 out of 2076 schools
(Top 10%)
(Top 10%)
Showing 2013–2023. Full 14-year historical data available below ↓
Math Test Scores (% Proficient)
61%
40%
Showing 2013–2023. Full 14-year historical data available below ↓
Reading/Language Arts Test Scores (% Proficient)
63%
43%
Showing 2012–2022. Full 13-year historical data available below ↓
Science Test Scores (% Proficient)
55-59%
38%
Student-Teacher Ratio
13:1
12:1
Showing 2016–2025. Full 39-year historical data available below ↓
Asian
8%
2%
Showing 2016–2025. Full 31-year historical data available below ↓
Hispanic
6%
9%
Showing 2016–2025. Full 29-year historical data available below ↓
Black
6%
15%
Showing 2016–2025. Full 32-year historical data available below ↓
White
74%
67%
Showing 2016–2025. Full 34-year historical data available below ↓
Two or more races
6%
6%
Showing 2016–2025. Full 14-year historical data available below ↓
All Ethnic Groups
Showing 2016–2025. Full 32-year historical data available below ↓
Chronically Absent Students
(22-23)11.7%
20.5%
Eligible for Free Lunch
9%
43%
Showing 2016–2025. Full 34-year historical data available below ↓
Eligible for Reduced Lunch
3%
7%
Showing 2016–2025. Full 27-year historical data available below ↓
School Statewide Testing
School District Name
Sports
Colors
Red and White
School Mascot
Cougars
Source: National Center for Education Statistics (NCES), MO Dept. of Education
Frequently Asked Questions
What is Castlio Elementary School's ranking?
Castlio Elementary School is ranked #169 out of 2,076 schools, which ranks it among the top 10% of public schools in Missouri.
What schools are Castlio Elementary School often compared to?
Castlio Elementary Schoolis often viewed alongside schools like Becky-david Elementary School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
61% of students have achieved math proficiency (compared to the 40% MO state average), while 63% of students have achieved reading proficiency (compared to the 43% MO state average).
How many students attend Castlio Elementary School?
847 students attend Castlio Elementary School.
What is the racial composition of the student body?
74% of Castlio Elementary School students are White, 8% of students are Asian, 6% of students are Hispanic, 6% of students are Black, and 6% of students are Two or more races.
What is the student-teacher ratio of Castlio Elementary School?
Castlio Elementary School has a student ration of 13:1, which is higher than the Missouri state average of 12:1.
What grades does Castlio Elementary School offer ?
Castlio Elementary School offers enrollment in grades Kindergarten-5 (No virtual instruction).
What school district is Castlio Elementary School part of?
Castlio Elementary School is part of Francis Howell R-III School District.
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