Mathematics review and corrections
Updated 30 September 2026. Dani Carl is the credited author. This site has not published verified mathematics qualifications, named independent course reviewers, or assessment-validation evidence. A course listing is not proof of independent review.
What is available to inspect
Product pages distinguish student and teacher PDFs and include manuscript openings and PDF page previews. These are limited samples. They do not establish the correctness or completeness of a whole course.
Corrections in progress
The website no longer certifies mastery from ten answers or verifies scratchpad mathematics. Draft practice hints are bound to fixed examples and complete solutions require an explicit reveal.
Source corrections dated 30 September 2026 clarify rounding to a chosen place (Grade 3), the final divisor in Euclid's algorithm including divisible pairs (Advanced Math 7), and the limits of substitution, factoring and leading-term rules (AP Calculus BC). Both editions of these courses have been rebuilt with those corrections. Downloadable PDF samples preserve exact pages from the paid files; each sample pack gives the edition revision, full SHA-256 hashes and physical page mapping. HTML previews reflow manuscript content. Independent educator review remains pending.
Report an error
Email hello@danicarl.com with the course, student or teacher edition, file date/version, page, exercise and proposed correction. Use synthetic examples and omit learner names or other personal information. Reports require content review before a revised edition is announced. No response deadline is promised.