California Achievement Test (CAT): What It Is, Who Takes It, Format, Scoring, and How Homeschool Families Use It
California Achievement Test (CAT) guide: format, subjects (Reading, Language, Math), grade levels K-12, scoring, cost, ordering for homeschool annual testing.

The California Achievement Test (CAT) is one of the most widely used standardized achievement tests in the United States, particularly popular among homeschool families. Originally developed by CTB/McGraw-Hill, the test measures student academic achievement in core subjects — Reading, Language, Math, Spelling, and Study Skills — using norm-referenced scoring that compares each student's performance to a national sample. Multiple editions exist, with CAT/5 and CAT/6 being the most common versions used today.
For homeschool families, the CAT serves a specific purpose: meeting state requirements for annual standardized testing. Many states (Pennsylvania, Hawaii, New York, North Dakota, and others) require homeschooled students to be tested annually using a state-approved standardized test. The CAT is among the most commonly approved tests because of its long-standing reputation, comprehensive coverage, and reasonable cost.
The test format is paper-based, multiple-choice (mostly), and untimed in homeschool settings (though typical completion is 1.5-2 hours). Different levels match different grade ranges: Level A for K-1, Level B for 2-3, Level C for 4-5, Level D for 6-7, Level E for 8-9, Level F for 10-12. Each level tests grade-appropriate content.
Subjects covered vary by level. Lower levels (K-3) focus on Reading, Language, Math, and Spelling. Higher levels add Study Skills and other components. Total testing time runs 1.5-2 hours typically. Untimed administration allows students to work without time pressure.
Scoring uses national norms. Your child's raw score is compared to a national sample of students at the same grade. Scores reported include: Percentile rank (where your child falls in the 100-point distribution), Grade equivalent (what grade level your child performs at), Stanine (1-9 scale), Normal Curve Equivalent (NCE).
Cost for homeschool families is reasonable: $25-50 per student for most testing services. Independent testing administrators handle the test administration, scoring, and reporting. Some services include consultation; others are bulk-rate testing.
This guide covers the California Achievement Test in detail — its history, current versions, format, subjects, scoring, how to order, and how homeschool families effectively use it. It's intended for homeschool parents, evaluators considering testing options, and educators familiar with standardized testing.
Key Test Information
- Publisher: Originally CTB/McGraw-Hill (now various successors)
- Type: Norm-referenced standardized achievement test
- Format: Paper-based, multiple-choice (mostly), untimed in homeschool
- Grade levels: K-12 (specific levels for grade ranges)
- Subjects: Reading, Language, Math, Spelling, Study Skills (varies by level)
- Time required: 1.5-2 hours typical
- Cost: $25-50 per student (homeschool services)
- Common editions: CAT/5 (1992), CAT/6 (2003)
- Why homeschool families use: Meets state annual testing requirements
- Scoring: Percentile, grade equivalent, stanine, NCE
- Approved in: Most states' homeschool requirements
- Alternatives: Iowa Test (ITBS), Stanford Achievement, TerraNova
What the California Achievement Test measures. Each subject area tests specific academic skills at grade-appropriate levels.
Reading. Tests reading comprehension across passages of varying length and complexity. Identifies main ideas, supporting details, vocabulary in context, inferences, drawing conclusions. Lower levels include word recognition and decoding; higher levels emphasize comprehension of complex texts.
Language. Tests grammar, usage, mechanics, and sentence structure. Topics include: parts of speech, subject-verb agreement, pronoun reference, punctuation, capitalization, sentence types, paragraph organization, writing mechanics. Builds from simple sentence structure at lower levels to complex grammatical analysis at upper levels.
Math. Computational skills, problem-solving, and number sense. Topics include: basic arithmetic (lower levels), fractions, decimals, percents, geometry, measurement, statistics, simple algebra (upper levels). Word problems test application of math to real situations.
Spelling. Recognition of correctly spelled vs incorrectly spelled words. Multiple-choice format presents word options; student selects the correct spelling. Grade-appropriate vocabulary at each level.
Study Skills (upper levels). Tests skills like reading comprehension of charts and graphs, using reference materials, interpreting maps and diagrams, organizing information. Develops in importance at middle school and high school levels.
Vocabulary. Some editions include vocabulary as a separate section. Word meanings, synonyms, antonyms, vocabulary in context. Develops grade-appropriate language skills.
Listening (lower levels). Some early levels include listening comprehension. Audio passages followed by comprehension questions.
Mathematics applications. Beyond computation, this tests applying math to solve real-world problems. Geometry, measurement, data interpretation, problem-solving.
The specific subjects tested depend on the level. Verify with your testing service which subjects are included for your child's grade level.

CAT Subjects by Level
Comprehension, vocabulary, main ideas, inferences. All levels K-12.
Grammar, mechanics, sentence structure, paragraph organization. All levels.
Computation, problem-solving, number sense. Lower: arithmetic. Higher: algebra, geometry.
Recognition of correctly spelled words. All levels K-12. Grade-appropriate vocabulary.
Charts, graphs, reference use, organizing information. Upper levels primarily.
Audio passages followed by questions. Lower levels K-3.
How homeschool families use the California Achievement Test. The CAT is a popular choice for several reasons.
State testing requirements. Many states require homeschooled students to undergo annual standardized testing. States with such requirements include: Pennsylvania (requires evaluation in grades 3, 5, 8 and at exit), Hawaii (annual K-12), New York (annual for high school graduation), Tennessee (regular for some homeschool methods), North Dakota (annual), Oregon (regular), Colorado (regular), Minnesota (regular), and others. The CAT is among the most commonly approved tests.
Private school placement. Some private schools use the CAT (or similar) to evaluate incoming homeschool students. Test scores help with placement decisions. Some schools require minimum scores for admission.
Identifying learning gaps. Even if testing isn't required, the CAT provides valuable information about your child's academic progress. Areas where scores are below grade level highlight gaps to address. Strong areas confirm effective homeschool teaching.
Documentation for record-keeping. Test results provide formal documentation of academic progress. Useful for: showing progress over years, demonstrating successful homeschool to outside parties, supporting college applications later.
Self-assessment tool. Many homeschool families use CAT not because of state requirements but because they want feedback on their teaching. The objective comparison to national norms provides perspective unavailable through curriculum evaluation alone.
Cost-effective testing. At $25-50 per student, the CAT is affordable. Compared to private psychological testing ($300+) or other comprehensive evaluations, CAT provides substantial information at low cost.
For homeschool families considering CAT testing, the key decision points are: which testing service to use, whether to take the test in-home or at a testing site, how to interpret and use the results, and how to integrate test data with curriculum decisions.
Common ordering process: Contact a homeschool testing service. Provide your child's information. Pay the test fee. Receive the test materials. Administer the test (untimed). Return the test for scoring. Receive results in 2-4 weeks. Use the results for state submission if required.
CAT Use Statistics
How to order and administer the California Achievement Test. The process is straightforward.
Step 1: Choose a testing service. Multiple services offer CAT testing for homeschool families: BJU Press Testing & Evaluation, FLO (Family Learning Organization), Seton Home Study, Christian Liberty Press, Bob Jones University Press. Choose based on: cost, results turnaround, customer service reputation, whether they're approved in your state, additional services offered.
Step 2: Determine your child's level. The CAT has different levels for different grade ranges: Level A (K-1), Level B (2-3), Level C (4-5), Level D (6-7), Level E (8-9), Level F (10-12). Order the level matching your child's current grade.
Step 3: Place the order. Contact the testing service. Provide: child's name and date of birth, current grade level, your contact information, payment.
Step 4: Receive test materials. The service ships the test booklet, answer sheet, and instructions. Includes any required test administration manual.
Step 5: Administer the test. Read the instructions carefully. Follow exactly. The test is untimed for homeschool families. Common practice: administer over 1-3 sessions for younger children, single session for older children. Provide a quiet, focused environment.
Step 6: Return for scoring. Send the completed answer sheet back to the testing service (usually with a prepaid return envelope). The service handles scoring.
Step 7: Receive results. The service sends the scoring report — typically 2-4 weeks after receiving the test. Includes: each subject's percentile rank, grade equivalent, stanine, NCE, comments, comparison to national norms.
Step 8: Submit to state if required. If your state requires annual test results, submit per state requirements. Most states have specific filing procedures and deadlines.
Step 9: Use the results. Review with your child. Identify strengths to celebrate and gaps to address. Use to inform next year's curriculum decisions.

CAT Testing Process
Step 1: Choose Service
Step 2: Determine Level
Step 3: Place Order
Step 4: Receive Materials
Step 5: Administer
Step 6: Return
Step 7: Receive Results
Step 8: Submit & Use
Interpreting CAT test scores. Understanding the report helps you use it effectively.
Percentile rank. Where your child falls compared to a national sample of same-grade students. 50th percentile = average. Above 50 = above average. Below 50 = below average. Most homeschoolers score in the 60-90 percentile range. Don't be discouraged by individual subject scores below 50 — focus on the overall pattern and trends over time.
Grade equivalent. The grade level at which your child performs. 4.5 means mid-fourth grade level. This is helpful but can be misleading — a 6th grader scoring at 9.5 grade equivalent doesn't necessarily belong in 9th grade. Use as one data point.
Stanine. 1-9 scale: 1-3 below average, 4-6 average, 7-9 above average. Less commonly emphasized than percentile.
Normal Curve Equivalent (NCE). 1-99 scale that's mathematically more useful for some calculations. Like percentile but on a continuous scale that allows averaging.
Standard age scores. Some reports include this. Compares to age-matched peers rather than grade-matched.
Confidence intervals. Some reports show a range rather than single score. The score has measurement error; the range represents likely true score.
Patterns to look for. Consistent grades across subjects: balanced learning. One subject significantly stronger: a strength to leverage. One subject significantly weaker: an area to address. Steady improvement year over year: effective teaching. Decline over time: needs attention. Variation by subject within a child: normal — most children have strengths and challenges.
What's normal range. Average homeschoolers score in the 55-85 percentile range. Below 50th percentile is below average but not necessarily problematic. Above 85th percentile is above average. Don't compare your child to test averages — every child has different strengths.
What's concerning. Substantial decline year over year (often indicates learning issues). Persistent low scores below 30th percentile (may indicate need for evaluation). Wide variation between subjects suggesting unbalanced learning.
Don't over-interpret. The CAT is one snapshot of one day. Many factors affect the score: health, sleep, focus, test anxiety. Use the data alongside your own observations of your child's learning.
Score Interpretation
Where child falls in 100. 50th = average. 60-90 typical for homeschoolers.
Grade level performance. 4.5 = mid-fourth grade. Don't over-interpret.
Less common metric. 4-6 average. 1-3 below. 7-9 above.
Like percentile but on continuous scale. Useful for averaging across tests.
Balanced or specific strength/weakness. Year-over-year trends.
One day's snapshot. Combined with observations gives fuller picture.
Comparing the California Achievement Test to alternatives. Other standardized tests are available.
Iowa Test of Basic Skills (ITBS). Popular alternative. Similar subjects and format. Published by Riverside (now HMH). Comparable scoring. Approximately same cost. Slightly different difficulty profile in some sections. Choose between CAT and ITBS based on familiarity, your state's approval, and your testing service's offerings.
Stanford Achievement Test (SAT 10). Now published by Pearson. More comprehensive in some areas. Often slightly more expensive ($35-60). Less commonly used in homeschool. Better known in private school settings.
TerraNova. The successor to CAT/6. Published by McGraw-Hill (now CTB). More modern editions. Computer-based options available. Slightly higher cost. May be more contemporary in content.
Common Core Aligned tests. Some newer tests align specifically with Common Core State Standards. May be more relevant for college prep but less universally accepted in homeschool settings.
Stanford Diagnostic Reading Test (SDRT) and Math Test. Diagnostic versions for identifying specific learning issues. More expensive ($100-200) but provide deeper analysis. Use when looking for specific issues, not for annual general assessment.
For most homeschool families, CAT is sufficient. Switching tests year to year provides less continuity than sticking with one. If you start with CAT, generally continue with CAT.
Choosing the right test depends on: state-approved tests (verify your state's list), cost considerations, familiarity (yours and your child's), test format preferences (paper vs computer), specific concerns to investigate (general assessment vs diagnostic).
The differences between tests are smaller than commonly perceived. The CAT, ITBS, and SAT 10 all measure similar academic achievement, all use similar norm-referenced scoring, and all serve homeschool annual testing requirements well. Choose based on practical factors rather than expecting major differences in outcomes.

Standardized Test Options
Cost: $25-50
Format: Paper-based, multiple-choice
Subjects: Reading, Language, Math, Spelling, Study Skills
Why popular: Long-standing reputation, affordable, widely accepted
Best practices for using the California Achievement Test effectively.
Practice 1: Maintain a consistent testing schedule. Annual testing, same time of year, provides the most useful longitudinal data. Spring is most common — close to academic year end.
Practice 2: Don't over-prepare. The CAT is designed to measure current achievement, not test-taking skill. Excessive preparation distorts the picture. Some general test familiarity is fine (knowing what to expect) but cramming on test content defeats the purpose.
Practice 3: Choose testing conditions wisely. Quiet, well-lit, comfortable environment. Free from distractions. Your child should be well-rested and well-fed. Avoid testing during stressful family periods.
Practice 4: Allow your child to relax. Some children get test anxiety. Reassure them that the test is for your information, not for evaluating them as a person. Help them approach it as just another school activity.
Practice 5: Use results constructively. Celebrate strengths. Address specific gaps. Don't compare child to siblings or to standardized norms in ways that undermine self-esteem.
Practice 6: Look at trends over time. A single year's scores have measurement error. The trend over 3-5 years shows real patterns. Don't make major curriculum changes based on single-year results.
Practice 7: Keep records. Save test reports. Useful for: tracking long-term progress, demonstrating successful homeschool, future college applications, identifying patterns.
Practice 8: Don't equate scores with intelligence. The CAT measures specific academic achievement, not intelligence or potential. Many factors affect test scores beyond intelligence.
Practice 9: Combine with other assessments. CAT scores work best alongside: your daily observations of learning, curriculum-based assessments, work samples, occasional informal evaluations.
Practice 10: Use the data to inform, not dictate. Test results inform your decisions about curriculum and teaching approach. They shouldn't dictate them. You know your child best.
The temptation to drill your child on potential test content before the CAT is strong but counterproductive. The test is designed to measure current achievement — not test-prep skill. Excessive preparation produces artificially inflated scores that mask actual learning gaps. Light familiarization (knowing what to expect, going over a sample question) is fine. Drilling specific content extensively defeats the purpose of standardized testing. Trust the test to measure what it's designed to measure; trust your homeschool teaching to have done the actual education.
Common questions about the California Achievement Test.
Q: Is the CAT still administered? A: Yes, though specific editions have changed over time. CAT/5 and CAT/6 are still widely available through homeschool testing services. Some services use slightly different but equivalent versions. The basic California Achievement Test concept and approach continues.
Q: Which states accept CAT for homeschool testing? A: Most states with homeschool testing requirements accept CAT. Verify with your state's homeschool law before testing. State homeschool organizations (HSLDA, state-specific groups) maintain current lists of approved tests.
Q: When should I test my child? A: Spring (April-June) is most common, near the end of the school year. Allows you to assess learning from the year. Avoid testing during stressful periods (illness, family disruption). Annual testing provides the most useful data; some families test less frequently.
Q: Can my child fail the CAT? A: There's no fail/pass — it's a norm-referenced test. Scores are reported as percentiles, grade equivalents, etc. Below-average scores indicate areas to address but aren't 'failure.' Don't frame the test as something to pass or fail.
Q: How is the CAT different from a state test? A: State tests (like California's CAASPP, Florida's FCAT) are criterion-referenced — they test whether students have mastered specific state standards. The CAT is norm-referenced — it compares to a national sample. For homeschool annual testing requirements, the CAT is typically more flexible and accepted in more states than state-specific criterion tests.
Q: Should I have my child take the same test every year? A: Usually yes. Continuity of testing provides clearer long-term tracking. Switching tests year to year makes comparison harder. Stick with CAT (or your chosen test) for multiple years.
Q: What if my child's scores are very low? A: Below 30th percentile in multiple subjects warrants attention. Consider: re-evaluating teaching approach, consulting with a homeschool support group, considering professional evaluation if learning disabilities are suspected. Don't panic — many factors contribute to low scores, and one year's results don't determine your child's potential.
CAT Pros and Cons
- +CAT has a publicly available content blueprint — you know exactly what to prepare for
- +Multiple preparation pathways accommodate different schedules and budgets
- +Clear score reporting shows specific strengths and weaknesses
- +Study communities share current insights from recent test-takers
- +Retake policies allow recovery from a difficult first attempt
- −Tested content scope requires substantial preparation time
- −No single resource covers everything optimally
- −Exam-day performance can differ from practice test performance
- −Registration, prep, and retake costs accumulate significantly
- −Content changes between versions can make older materials less reliable
ACHIEVEMENT Questions and Answers
The California Achievement Test serves homeschool families well as a reliable, affordable way to measure academic progress and meet state requirements. The $25-50 annual investment and 1.5-2 hour testing time produces useful data about your child's academic standing relative to national norms. With practical use of results — celebrating strengths, addressing gaps, tracking trends over years — the CAT becomes a valuable tool rather than just a regulatory requirement.
For homeschool families, the recommended approach is: choose a testing service with good reviews and state approval, test annually at consistent time of year, administer in calm conditions without over-preparing, review results constructively with your child, and use the data to inform but not dictate curriculum decisions. Combined with daily teaching observations and curriculum-based assessments, the CAT provides one important perspective on your child's homeschool education progress.
About the Author
Attorney & Bar Exam Preparation Specialist
Yale Law SchoolJames R. Hargrove is a practicing attorney and legal educator with a Juris Doctor from Yale Law School and an LLM in Constitutional Law. With over a decade of experience coaching bar exam candidates across multiple jurisdictions, he specializes in MBE strategy, state-specific essay preparation, and multistate performance test techniques.