California’s Largest Exam-Prep School Since 1985
Founded by Educators. Built for the Trades.
For 40+ Years, Contractors State License Services has helped 200,000+ California tradespeople turn skill into a license - with a 99% first-time pass rate and a 100% Money-Back Guarantee.
40+ Years
In Business Since 1985
200,000+
Students Licensed
99%
First-Time Pass Rate
25
California Locations
Founder photo
David Mizener
David Mizener
Founder & creator of the Mizener Method
Our Story
A School Started by Teachers, Not Lawyers
Contractors State License Services opened its doors on February 4, 1985, in Van Nuys, California. At the time, most licensing schools were run by lawyers or insurance brokers looking to cross-sell - not by people who understood teaching. CSLS was different. It was founded by educators who saw a real problem: skilled tradespeople who could wire a house or frame a building often struggled with the abstract, test-taking format of the CSLB exam.
That single insight, that trade competence and test performance are two different skills, became the foundation of everything we do. Founder David Mizener built a teaching approach around it - the Mizener Method - and what began as one classroom in Van Nuys has grown into California’s largest contractor exam-prep network, serving 200,000+ students across 25 locations statewide, with online, home-study, and crash-course formats for working professionals.
How We Teach
The Mizener Method
Our proprietary teaching methodology was developed for one purpose: to close the gap between knowing the trade and passing the exam. It tackles test anxiety head-on - teaching you not just the material, but how to take the exam: construction math, test-taking strategy, and the Law & Business knowledge that trips up even experienced contractors.
The CSLB exam is a two-part, seven-hour test - Law & Business and a trade-specific exam. The Mizener Method prepares you for both, across every license classification the state offers. It’s why 99% of our students pass on the first try, backed by our 100% Money-Back Guarantee.
Law & Business
The contracts, finance, and code knowledge every classification is tested on.
Construction Math
The calculations the exam demands - broken down for hands-on learners.
Test-Taking Skills
Strategy and confidence that beat the test anxiety experience can’t.
Every Classification
Trade-specific prep for all 46 CSLB classifications.
What We Stand For
Our Core Values
The principles that have guided how we teach, and how we treat every student, since 1985.
Excellence in Education
We are educators first, founded by teachers, not lawyers or insurance brokers. The proprietary Mizener Method is built on 41 years of understanding how hands-on learners master abstract material.
Accessibility & Inclusion
Every aspiring contractor deserves quality prep - across 25 California locations, four learning formats, and a fully localized Spanish-language program built for the trades, never just translated.
Accountability
We back our promise with action. The Real Pass Guarantee means if a student fails, we pay for their retake. Not a gimmick - a structural commitment that ties our success to yours.
Empowerment & Dignity
A license is more than a credential - it is economic autonomy, professional respect, and a family legacy. We treat every enrollment as a life investment and partner with you through the whole journey.
Community
With 200,000+ graduates since 1985, we are California's largest contractor exam-prep community. Rooted in the trades, speaking the language of the trades, existing to serve the trades.
Our Team
Meet the CSLS Family
Behind every 99% first-time pass is a team of educators, advisors, and support staff who treat your license like it’s their own. This is the family that’s been backing California’s contractors since 1985.
Clases de Español
A Spanish Program Built for the Trades - Not Translated
A significant part of California’s construction workforce speaks Spanish as a first language. So we built a parallel program that is culturally localized, never simply translated - instruction rooted in familia, dignidad, and legado, meeting Spanish-speaking students where they are.
Explore Our ProgramsThe Full Journey
More Than a Test-Prep School
Over the decades, we’ve grown into the gateway institution for a contractor’s entire professional journey.
Exam Prep
Four formats (in-school, live online, home study, and crash course) for every classification.
View programs →Specialty Seminars
EPA RRP lead-paint certification, mold remediation, blueprint reading, ICC building codes, and more.
Browse seminars →Business Services
Corporation & LLC formation, contractor bonds & renewals, and construction insurance.
Learn more →Office Hours (Pacific)
- Monday – Wednesday
- 9:30 AM – 6:00 PM
- Thursday
- 9:30 AM – 6:30 PM
- Friday
- 8:30 AM – 4:30 PM
- Saturday – Sunday
- Closed
Since 1985
40+ Years
200,000+
Students Licensed
99% Pass Rate
First-Time
100% Money-Back Guarantee
Tuition Refund
