Scope: "Flash Cards & Reading Toys" (supplies > play > educational-science > flash_cards) — paper/cardstock flash card sets for drilling letters, numbers, sight words, phonics and vocabulary, AND battery/mechanical interactive reading toys (stylus+patterned-book systems and button/sound toys) that teach early reading. Excludes abacuses/manipulatives, astronomy toys and science/nature toys (sibling leaves in catalog.json).

Seed: Flash-cards equivalent of the tyre treadwear example = card_count/card_size spec that looks like a plain number but experts read against the Leitner spaced-repetition method (a pack is a study tool, not just a stack). Persona (industrial designer) would first notice that "light-up" and "pop-up" cards are paper-engineering tricks (die-cut stencils + a flashlight, folded pop-ups), not electronics — the real electronics/cost jump is the stylus-and-dot-pattern reading systems (LeapFrog Tag/LeapReader/LeapStart lineage), which is where the brand locks a buyer into a non-interchangeable book library.

Sources:
[wikipedia_flashcard] https://en.wikipedia.org/wiki/Flashcard — defines flashcard, active recall, Leitner system | fetched excerpt: "In this method, flashcards are sorted into groups according to how well the learner knows each one... the schedule of repetition was governed by the size of the five partitions... 1, 2, 5, 8, and 14 centimetres"
[wikipedia_spaced_repetition] https://en.wikipedia.org/wiki/Spaced_repetition — spacing effect, increasing review intervals | fetched excerpt: "Newly introduced and more difficult flashcards are shown more frequently, while older and less difficult flashcards are shown less frequently in order to exploit the psychological spacing effect."
[wikipedia_sight_word] https://en.wikipedia.org/wiki/Sight_word — sight-word vs phonics pedagogy, Dolch word list | fetched excerpt: "Sight words account for a large percentage (up to 75%) of the words used in beginning children's print materials" and "a 2017 study in England... concluded that phonics is more effective"
[wikipedia_cpsia] https://en.wikipedia.org/wiki/Consumer_Product_Safety_Improvement_Act — lead/phthalate limits, small-parts third-party testing deadline | fetched excerpt: "Small parts | November 17, 2008 | February 15, 2009" (third-party testing accreditation/requirement table)
[wikipedia_astm] https://en.wikipedia.org/wiki/ASTM_International — ASTM F963 mandatory under CPSIA | fetched excerpt: "All toys sold in the United States must meet the safety requirements of ASTM F963, Standard Consumer Safety Specification for Toy Safety, as part of the Consumer Product Safety Improvement Act (CPSIA) of 2008."
[wikipedia_leapfrog] https://en.wikipedia.org/wiki/LeapFrog_Enterprises — stylus+dot-pattern reading systems, ages, non-interchangeable book libraries | fetched excerpt: "Tag Reading System – a specially designed stylus that has a small infrared camera at the tip that 'reads' letters, words and symbols printed on the special dot-patterned pages... designed to help children aged 4–8" and "LeapStart system is not compatible with the earlier Tag and LeapReader books."
[wikipedia_anoto] https://en.wikipedia.org/wiki/Anoto — generic dot-pattern optical pen technology, lists Tag as a licensee | fetched excerpt: "It works by recognizing a non-repeating dot pattern printed on the paper... Models include: ... Tag (LeapFrog)"
[schoolzone_catalog] https://www.schoolzone.com/flash-cards — product range: alphabet, numbers, sight words, phonics, math-fact operations, bilingual, word families, picture words, write&reuse, pop-up, puzzle, game-deck cards | fetched excerpt: product handle/name list incl. "Phonics Made Easy Flash Cards", "Sight Words Flash Cards", "Bilingual Alphabet Flash Cards", "Three-Letter Words Puzzle Cards", "Go Fish Alphabet Game Cards"
[schoolzone_alphabet] https://www.schoolzone.com/products/alphabet-flash-cards — standard spec sheet | fetched excerpt: "Size: 3.25\" x 5.5\" Contents: 56 Alphabet Cards, 3 Index Cards, 1 Parent Card"; tags "Age 3/4/5/6"; picture-word pairing ("K is for Kite")
[schoolzone_popup] https://www.schoolzone.com/products/animal-alphabet-pop-up-learning-cards — large-format pop-up spec | fetched excerpt: "Size: 5.5\" x 7.5\" Contents: 26 Pop-Up Alphabet Cards"
[schoolzone_lightup] https://www.schoolzone.com/products/bedtime-alphabet-light-up-learning-cards — stencil/shadow-play format, not battery electronics | fetched excerpt: "Use the handy mini flashlight included in the package to shine light through the clever cutouts... Or flip the cards over to reveal pieces to six different puzzles."

Branches: product_type -> flash_cards routes to learning_focus, card_count, card_size, card_format, bilingual_or_monolingual, phonics_vs_sight_word_approach, play_mode, picture_support, operation_scope (sentence: schoolzone_catalog shows these vary only across the paper-card line, not the electronic line). product_type -> electronic_reading_toy routes to reading_mechanism, interaction_feedback_type, book_library_compatibility and makes operation_scope/card_count/card_format irrelevant (sentence: wikipedia_leapfrog describes a stylus+book system with no "card count" or "card format" analogue). reading_mechanism -> pen_and_book_system makes book_library_compatibility relevant (sentence: wikipedia_leapfrog — Tag/LeapReader/LeapStart books are not cross-compatible, so the pen you buy locks you into its own book line).

Noise: "weight"/package dimensions on schoolzone spec sheets — logistics, not an expert facet. "SKU"/"price" fields — excluded by rule. Battery type/voltage for stylus pens — wanted to add as a facet but no two sources confirmed the actual battery spec for current pen systems (only found a tablet's battery life, a different sub-line), so left out rather than guess. Ring-binding/hole-punch/lamination terminology — not confirmed on any fetched spec sheet, dropped rather than assumed from the template's comb/brush example. "Dolch word list" — real curated sight-word list, kept only as a vocabulary term since the single mention found was a nav-box link with no supporting body text to cite as a fact.

Corrections (2026-10-26):
Added facet visual_feedback_type (audio_only_no_screen / screen_with_animations) for electronic reading toys, sourced to leapfrog_leapstart_catalog ("features on-screen animations... any LeapStart system with a screen") and prnewswire_leapstart3d ("interactive 3D-like display"); wired into product_type's flash_cards branch makes_irrelevant.
Added play_mode to product_type's electronic_reading_toy branch makes_irrelevant (a reading toy has no multiplayer game-deck mode).
Reworded learning_focus's question/cold_start_question to name all five values, including shapes_colors_and_concepts.
Tightened age_range max from 10 to 8 and rewrote typical text: the old age-9 anchor (LeapPad) is a general tablet outside this register's reading_mechanism values; wikipedia_leapfrog's own in-scope ceiling is the Tag Reading System at age 4-8.
Dropped the "Dolch word list" vocabulary entry: no fetched source cites it from body text, only an uncited nav-box link.