Best charter schools in Katy (2025)
Publicly funded charter schools. Ranked by the Success Index (US) from official American data; 9 schools in Katy, Texas. Rank positions shown on each profile are within United States and Texas.
- 176Calvin Nelms MiddleKaty · Charter Middle72% Math proficiency · 160 students
- 271Harmony School of Innovation - KatyKaty · Charter High85% Math proficiency · 876 students
- 371Calvin Nelms H SKaty · Charter High64.5% Math proficiency · 183 students
- 469Harmony Science Academy-KatyKaty · Charter Elementary67% Math proficiency · 1,347 students
- 566Aristoi Classical Upper SchoolKaty · Charter High45% Math proficiency · 664 students
- 660Aristoi Classical AcademyKaty · Charter Elementary47% Math proficiency · 431 students
- 744Iltexas Katy ElKaty · Charter Elementary43% Math proficiency · 936 students
- 843Harmony School of Excellence - KatyKaty · Charter Elementary54.1% Free/reduced-price lunch · 1,123 students
- 942Iltexas Katy MiddleKaty · Charter Middle37% Math proficiency · 459 students
| # | School | Sector | Success Index (US) | Key result | Students |
|---|---|---|---|---|---|
| 1 | Calvin Nelms Middle Katy · Middle · Grades 6–8 | Charter | 76.0 Top 25% | 72% Math proficiency | 160 |
| 2 | Harmony School of Innovation - Katy Katy · High · Grades 8–12 | Charter | 71.2 Top 25% | 85% Math proficiency | 876 |
| 3 | Calvin Nelms H S Katy · High · Grades 9–12 | Charter | 70.5 Top 25% | 64.5% Math proficiency | 183 |
| 4 | Harmony Science Academy-Katy Katy · Elementary · Grades PK–7 | Charter | 69.2 Top 25% | 67% Math proficiency | 1,347 |
| 5 | Aristoi Classical Upper School Katy · High · Grades 5–12 | Charter | 65.9 Top 50% | 45% Math proficiency | 664 |
| 6 | Aristoi Classical Academy Katy · Elementary · Grades K–4 | Charter | 59.9 Top 50% | 47% Math proficiency | 431 |
| 7 | Iltexas Katy El Katy · Elementary · Grades K–5 | Charter | 44.1 Lower 50% | 43% Math proficiency | 936 |
| 8 | Harmony School of Excellence - Katy Katy · Elementary · Grades PK–8 | Charter | 43.2 Lower 50% | 54.1% Free/reduced-price lunch | 1,123 |
| 9 | Iltexas Katy Middle Katy · Middle · Grades 6–8 | Charter | 42.4 Lower 50% | 37% Math proficiency | 459 |
Calvin Nelms Middle in Katy leads the 2025 list of charter schools in Katy with a Success Index (US) of 76.0. Of the 9 schools shown, 9 are charter.
For the full picture see the wider Texas charter schools rankings, every school on the Katy page, or the comparison tool to put a shortlist side by side.
Free academic assessment
Is your child on grade level in reading and math?
Success Tutoring offers personalised English and math tutoring from Kindergarten to Grade 12. Start with a free online assessment and a clear plan for the year ahead.
- Personalised learning plan mapped to the Australian Curriculum
- English & Maths from Kindergarten to Year 12
- Flexible memberships, no lock-in contracts
- Centres across NSW, VIC, QLD, WA, SA and ACT
Frequently asked questions
What is the best charter school in Katy?
Calvin Nelms Middle in Katy, Texas ranks first among charter schools in Katy with a Success Index (US) of 76.0 out of 100 (Enrollment: 160).
How are charter schools in Katy ranked?
Each school's Success Index (US) combines 4 factors: math proficiency (30%), reading proficiency (30%), community advantage (fewer free/reduced-price lunch) (25%), students per teacher (15%). Each factor is a percentile against schools of the same type across United States. Schools with fewer than 60 students are excluded from rankings.
Are these 2025 rankings official?
No. They are computed by Success Tutoring from official American data (Urban Institute Education Data Portal (NCES CCD, EDFacts); NCES Common Core of Data). States set their own assessments and proficiency cut scores, so proficiency rates are most comparable within a state. Use the state rankings for like-for-like comparisons.