US pre-K–8 math standards

Everything learned building Mathness (mathness.app), a generated pre-K–8 worksheet site aligned to Common Core, four own state frameworks, 55 state editions and ten curricula, condensed for reuse. Facts are as of 2026-10-01 for K–5 and 2026-10-06 for grades 6–8: standards change every school year, so check the watch list in references/landscape.md before quoting a state's current set.

Words used here

• Set: one standards framework as a view over your catalogue: grades → domains → standards, each in the set's own code with your own one-line summary. Common Core is one set; each state is another.
• Own set: a state framework written from scratch with its own codes and wording (Texas TEKS, Florida B.E.S.T., Virginia SOL, Maryland MCCRS 2025). Modelled in full and fit-reviewed row by row.
• Crosswalk: a state's every standard, in its own code, mapped to the Common Core codes it carries (same content, maybe another grade) and the sheets for what it moved or added (from). Rows are links-only: a row finds sheets through its mapped codes, never by its own code string.
• Edition: a derived set: Common Core under a state's name, a crosswalked state, or next school year's standards beside this year's.
• Home: the one row a set-only sheet is filed under (its own code), which fixes its grade and place in every set.
• Coverage: a sheet exists for a standard (enforced by a test). Fit: the sheets practise what the standard asks at its grade (judged by a reviewer): good, partial (a named part missing, or only a sheet 2+ grades off), mismatch.
• Fresh review: a fit review of every row with no earlier verdicts, the check on drifting incremental reviews.
• Pass: one batch of fit fixes (links, alternatives, sheets) followed by a re-review of only the rows it touched. Mathness numbered its crosswalk passes 1–13; "closed in pass 9" means that pass's re-review found the row good.
• Alternative: an activity offered in place of one of a sheet's sections (the seed picks one), adding coverage without lengthening the page.
• OVR, extra.tsv, NAMES, EXPLICIT (named in the state files): the first K–5 generator's tables (sheets for moved and new rows; links fit reviews added; edition titles; states whose rows carry their grade). That generator was lost; its links now sit in each research TSV's from and unlink columns, generated by scripts/crosswalk/gen.py (scripts/README.md).
• Representation: what a standard's wording requires beyond its topic: a model, a letter for the unknown, a drawing, an explanation, a unit of measure.
• Narrowed row: a standard that asks for a construction, derivation, proof or design, cut down to what a key can check and saying so on the row (seven in Common Core 6–8); it may stay partial by design.
• Hidden grade: a grade built and tested but not yet shown to visitors; its standards must all have sheets, and visitor-facing code reads only the live grades.