#1 Largest Private Schools in New Castle County, DE
Caravel Academy
Independent school · Grades Pre-K–12
1,120 students
Bear, DE
B+Overall grade1,120 students10 students per teacher
2026 lists
Largest Private Schools in New Castle County, DE
The private schools in New Castle County, DE with the most students. Top 39 of 39 schools.
#2 Largest Private Schools in New Castle County, DE
St. Mark's High School
Diocesan school · Grades 9–12
829 students
Wilmington, DE
BOverall grade829 students17 students per teacher
#3 Largest Private Schools in New Castle County, DE
Red Lion Christian Academy
Christian school (nondenominational) · Grades K–12
695 students
Bear, DE
AOverall grade695 students10 students per teacher
#4 Largest Private Schools in New Castle County, DE
Christ the Teacher Catholic School
Diocesan school · Grades Pre-K–8
524 students
Newark, DE
B-Overall grade524 students23 students per teacher
#5 Largest Private Schools in New Castle County, DE
St. Mary Magdalen School
Parish school · Grades Pre-K–8
467 students
Wilmington, DE
B+Overall grade467 students13 students per teacher
#6 Largest Private Schools in New Castle County, DE
St. John the Beloved School
Parish school · Grades Pre-K–8
459 students
Wilmington, DE
B-Overall grade459 students18 students per teacher
#7 Largest Private Schools in New Castle County, DE
The Tatnall School
Independent school · Grades Pre-K–12
457 students
Wilmington, DE
A+Overall grade457 students6 students per teacher
#8 Largest Private Schools in New Castle County, DE
Ursuline Academy, Lower
Independent Catholic school · Grades 3–8
456 students
Wilmington, DE
A+Overall grade456 students8 students per teacher
#9 Largest Private Schools in New Castle County, DE
Padua Academy
Diocesan school · Grades 9–12
424 students
Wilmington, DE
A+Overall gradeAll girls424 students11 students per teacher
#10 Largest Private Schools in New Castle County, DE
Immaculate Heart of Mary
Diocesan school · Grades Pre-K–8
406 students
Wilmington, DE
B-Overall grade406 students16 students per teacher
#11 Largest Private Schools in New Castle County, DE
The Independence School
Independent school · Grades Pre-K–8
384 students
Newark, DE
AOverall grade384 students8 students per teacher
#12 Largest Private Schools in New Castle County, DE
St. Elizabeth School
Diocesan school · Grades Pre-K–12
364 students
Wilmington, DE
BOverall grade364 students12 students per teacher
#13 Largest Private Schools in New Castle County, DE
St. Andrew's School
Episcopal school · Grades 9–12
320 students
Middletown, DE
A+Overall grade320 students6 students per teacher
#14 Largest Private Schools in New Castle County, DE
St. Annes Episcopal School
Episcopal school · Grades Pre-K–8
256 students
Middletown, DE
A+Overall grade256 students7 students per teacher
#15 Largest Private Schools in New Castle County, DE
St. Ann School
Parish school · Grades Pre-K–8
200 students
Wilmington, DE
BOverall grade200 students16 students per teacher
#16 Largest Private Schools in New Castle County, DE
Fairwinds Christian School
Baptist school · Grades Pre-K–12
173 students
Bear, DE
B+Overall grade173 students12 students per teacher
#17 Largest Private Schools in New Castle County, DE
St. Anthony of Padua Grade School
Diocesan school · Grades Pre-K–8
161 students
Wilmington, DE
A+Overall grade161 students9 students per teacher
#18 Largest Private Schools in New Castle County, DE
St. Edmond's Academy
Independent Catholic school · Grades Pre-K–8
158 students
Wilmington, DE
A+Overall gradeAll boys158 students9 students per teacher
#19 Largest Private Schools in New Castle County, DE
The Pilot School
Special education school · Grades K–8
136 students
Wilmington, DE
AOverall grade136 students4 students per teacher
#20 Largest Private Schools in New Castle County, DE
Concord Christian Academy
Baptist school · Grades Pre-K–12
136 students
Wilmington, DE
B+Overall grade136 students9 students per teacher
#21 Largest Private Schools in New Castle County, DE
Islamic Academy of Delaware
Islamic school · Grades Pre-K–8
124 students
Newark, DE
A+Overall grade124 students5 students per teacher
#22 Largest Private Schools in New Castle County, DE
Harvest Christian Academy New Castle
Christian school (nondenominational) · Grades Pre-K–12
100 students
New Castle, DE
B+Overall grade100 students9 students per teacher
#23 Largest Private Schools in New Castle County, DE
Harvest Christian Academy
Christian school (nondenominational) · Grades Pre-K–12
94 students
New Castle, DE
A+Overall grade94 students8 students per teacher
#24 Largest Private Schools in New Castle County, DE
Centerville Layton School
Independent school · Grades K–12
88 students
Wilmington, DE
AOverall grade88 students3 students per teacher
From official public records, updated October 2026.