Montessori Harbor Mesa School · Preschool, Costa Mesa
Montessori Harbor Mesa School is a licensed child care center in Costa Mesa, CA, licensed for up to 63 children and serving preschool-age children. It has held its California license since 2020. Since February 2021, state licensing staff have inspected it 2 times and investigated 2 complaints, 1 of them substantiated. The state issued 6 citations, 0 of them Type A (the most serious), most often for health & medication (2 of 6). 5 citations came in the last 12 months. Measured by weighted citations per inspection, it is #40 of 47 centers in Costa Mesa and has more citations per inspection than 88% of California licensed centers.
Inspection record
Every state visit
What inspectors cited most
Citations, newest first
Schedule TSP training for all staff. Send TSP sign-in to LPA. Staff in-service: Behaviors/include hands-on Send in-service sign-in to LPA. Basedon staff and children interview, C1 hit teachers, hit other children, kick things, throw things since 10/2025 and facility failed to prevent C1 from hurting others. This poses a potential danger to the health of the children in care.
Based on LPA observation, staff & child interview, and record review, the licensee did not comply with the section cited above in 1 out of 14 children. This poses a potential risk to the health, safety and/or personal rights of children in care.
Based on LPA observation, staff interview, and record review, the licensee did not comply with the section cited above in 1 out of 7 chidlren's files which poses a potential health, safety or personal rights risk to persons in care.
Based on LPA observation, staff interview, and record review, the licensee did not comply with the section cited above in 1 out of 7 children's files which poses a potential health, safety or personal rights risk to persons in care.
Based on LPA observation, staff interview, and record review, the licensee did not comply with the section cited above in 1 out of 7 children's medications, which poses a potential health, safety or personal rights risk to persons in care.
101700.3 California Lead Action Level at Child Care Centers (b) Testing results...comparing to the Action Level. (1) A result with values of 5.5 part per billion or greater shall be deemed an Action Level Exceedance. Director stated that facility followed Written Directives and submitted all required documentation including LIC 9275, 9276, plan of correction and details of steps taken to resolve the deficiency by due date This requirement was not met evidenced by: Lab report analysis water from Outlet E (6.2 parts per billion) taken on 06/17/2023 indicated levels of lead in exceedance. This poses a potential risk to the health, safety and personal rights of children in care. 8
How common are lead-in-water citations in Orange County? See the county-by-county report →
Complaint investigations
Facility staff are not preventing children from engaging in inappropriate behaviors towards other children.
How often are complaints about daycares in Orange County substantiated? See the county-by-county report →
About this center
Other licenses at this address
Common questions
Does Montessori Harbor Mesa School take infants?
Not under this license, which covers preschool-age children.
Has Montessori Harbor Mesa School had any serious violations?
No Type A citations since 2021. It has 6 Type B citations, listed above.
Have there been complaints about Montessori Harbor Mesa School?
California investigated 2 complaints since 2021 and substantiated 1. Allegations are shown only for substantiated complaints.
How does Montessori Harbor Mesa School compare with other daycares in Costa Mesa?
It is #40 of 47 centers in Costa Mesa by weighted citations per inspection, and has more citations per inspection than 88% of California licensed centers with enough inspection history to compare.
When was Montessori Harbor Mesa School last inspected?
Oct 9, 2025. No citations were issued during that visit.
How much does Montessori Harbor Mesa School cost?
California does not publish individual centers’ prices, so ask Montessori Harbor Mesa School for its current tuition. For comparison, the median full-time price at licensed centers in Orange County, which includes Costa Mesa, was $1,098 a month for preschoolers (about $1,390 today) in the state’s 2021 Regional Market Rate Survey.
Who runs Montessori Harbor Mesa School?
The licensee is Montessori Harbor Mesa School, and the administrator listed with the state is Giuliana De Frenza.
Licensed centers nearby
3013 Deodar Avenue, Costa Mesa · under 0.1 mi away · 8 spotsAbout typicalMesa Verde Preschool & Infant Center
3013 Deodar Avenue, Costa Mesa · under 0.1 mi away · 42 spotsMore citations than mostSeaside Costa Mesa Preschool
1701 Baker Street, Costa Mesa · 0.4 mi away · 70 spotsAmong the most citedPacific Academy
2987 Mesa Verde Drive E, Costa Mesa · 0.5 mi away · 60 spotsMore citations than mostNmusd Killybrooke Preschool
3155 Killybrooke Lane, Costa Mesa · 0.5 mi away · 24 spotsNo citationsInt'l Christian Montessori Academy Of Costa Mesa
2950 McClintock Way, Costa Mesa · 0.7 mi away · 22 spotsMore citations than most
Citations are quoted from California Department of Social Services inspection and complaint reports. Type A citations are the state’s most serious category (an immediate risk to children’s health, safety or personal rights); Type B citations are a potential risk. A citation is a finding about one rule, not a judgment about a center overall. Complaint allegations appear here only when the state substantiated them.
To read the full state reports, search facility number 304371431 on the California Care Facility Search. Data refreshed Oct 3, 2026.
Comparing centers? See how to choose a daycare: 30 questions to ask and a printable checklist.