Complete preparation guide for California's 30-Day Substitute Teaching Permit exam — what the law requires, exam format, content domains, and how to prepare efficiently.
California Assembly Bill 900 (AB-900), signed into law and codified in the California Education Code, created and expanded the 30-Day Substitute Teaching Permit. This permit allows individuals who have not completed a full California teaching credential to work as substitute teachers in California public schools for up to 30 days with a single teacher in a school year.
To qualify for the 30-Day Substitute Teaching Permit, candidates must meet educational requirements (typically a bachelor's degree) and pass a subject matter competency examination. The AB-900 exam is the qualifying test for this permit. It is administered by the California Commission on Teacher Credentialing (CTC) through approved testing providers.
The AB-900 permit is widely used across California school districts that face substitute teacher shortages, and passing the exam opens up employment opportunities throughout the state's public school system.
You need the 30-Day Substitute Teaching Permit if you want to serve as a substitute teacher in California and do not hold a valid California teaching credential or intern credential. The most common candidates include:
The AB-900 qualifying examination consists of 60 multiple-choice questions. All questions have a single correct answer from four options. The exam is typically administered in a computer-based format at approved testing centers, with a time limit that allows candidates ample time to carefully consider each question. Most testing providers allow approximately 90 minutes to 2 hours for the full exam.
Candidates must achieve a passing score on the AB-900 exam to qualify for the 30-Day Substitute Teaching Permit. The California Commission on Teacher Credentialing sets the passing standard based on a criterion-referenced approach — you must demonstrate a minimum level of knowledge across the tested content domains rather than simply outscoring other test-takers. The passing score is established through a standard-setting process involving educators and subject matter experts.
Score reporting: Most testing providers report results as pass or no pass immediately after the exam or within a few business days. A numerical score or percentage may also be provided for diagnostic purposes.
The AB-900 exam tests knowledge across several content areas relevant to effective substitute teaching in California classrooms. The exam is designed to verify that candidates possess foundational knowledge necessary to manage a classroom and support student learning in a temporary capacity.
This domain tests understanding of how students develop cognitively, socially, emotionally, and physically across grade levels. Questions assess knowledge of developmental milestones, how learning changes from elementary through secondary school, and how development affects behavior and classroom management needs. Candidates should understand major developmental theorists and how their frameworks apply to real classroom situations.
A significant portion of the AB-900 exam addresses classroom management — how substitute teachers establish order, maintain a productive learning environment, and respond to student behavior. Questions in this domain test knowledge of both proactive strategies (setting expectations, establishing routines) and reactive strategies (de-escalation, consequences, referrals).
This domain covers foundational instructional approaches that an effective substitute teacher should be able to implement when following lesson plans left by the regular classroom teacher. Questions assess knowledge of how to deliver instruction, differentiate for diverse learners, and assess student understanding during a lesson.
California classrooms are among the most diverse in the nation. The AB-900 exam includes questions on how substitute teachers can effectively support English Language Learners (ELLs), students with Individualized Education Programs (IEPs), students receiving 504 accommodations, and gifted or advanced learners.
This domain addresses the legal and ethical responsibilities of a substitute teacher. Questions cover mandatory reporting requirements, student confidentiality under FERPA, appropriate professional boundaries, and understanding the substitute's role within the school community.
Substitute teachers must be prepared to respond appropriately during health or safety emergencies. This domain tests knowledge of basic emergency procedures, first aid obligations, and how to handle situations such as lockdowns, fires, or medical emergencies in the classroom.
The AB-900 exam assumes basic familiarity with K–12 education principles. If you don't have a background in education, spend a few hours reviewing introductory concepts in child development, classroom management, and instructional theory before diving into practice questions. Even brief exposure to these foundational ideas will make the questions significantly more approachable.
Some questions on the AB-900 exam are specific to California law and policy. Make sure you understand California's mandatory reporting laws (including who is a mandated reporter and what triggers a report), the structure of California's credential system, and how California schools implement IEPs and 504 plans under federal IDEA and Section 504 requirements.
The most efficient way to prepare for any multiple-choice exam is through targeted practice. After studying a content domain, immediately test yourself with practice questions on that domain. Wrong answers are valuable — they tell you exactly which concepts to revisit. Review the explanation for every wrong answer, not just the correct one.
On the AB-900 exam, most questions have one clearly wrong answer and one clearly right answer, with two plausible distractors in between. Start by eliminating any option that involves endangering student safety, violating student privacy, or acting outside the substitute teacher's authority. Then choose the option that is most proactive, least escalatory, and most aligned with professional standards.
Most candidates find that 2–3 weeks of structured preparation is sufficient for the AB-900 exam, assuming they study for 30–60 minutes daily. The exam is not designed to be overly difficult — it tests whether you have basic competency, not advanced expertise. Prioritize daily consistency over marathon study sessions.
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Start Free Practice →Once you pass the AB-900 qualifying exam, you can apply for the 30-Day Substitute Teaching Permit through the California Commission on Teacher Credentialing (CTC) at ctc.ca.gov. The application process requires submitting official transcripts, the exam results, and an application fee. Once issued, the permit allows you to contact school districts directly about substitute teaching opportunities.
California school districts are always in need of qualified substitute teachers, and the 30-Day Substitute Permit is one of the most accessible routes into the California public school system. Many substitute teachers use the position as a stepping stone toward completing a full teaching credential.