99 Club Studio — v1.21 release notes
Date: 10 September 2026
Custom Worksheets — Year 6 Pie Charts
v1.21 adds a dedicated generated Pie Charts subsystem to /tools/99-club/custom/. The normal Year 6 curriculum family remains separate from opt-in reasoning and 11+/cross-topic Extension material.
Teacher-facing families:
- pie charts — interpret & construct — 21 stable subtypes / 84 deterministic pool entries;
- pie charts — reasoning & problem solving — 11 / 44;
- pie-chart reasoning (extension) — 5 / 20.
Total: 37 stable pie-chart subtypes / 148 deterministic pool entries.
The generated questions include qualitative sector comparison, fraction/percentage/angle interpretation, counts from totals, totals from known sectors, missing information, combined/all-other categories, differences, linked frequency/angle tables, mixed true/false statements, estimation, two-chart comparison, changed totals, merged-chart reasoning and accurate construction from frequency/percentage data.
The Extension family contains cross-representation and cross-topic structures such as pie-to-bar conversion, percentage/money contexts, external scoring rules and fraction arithmetic. These are deliberately not presented as ordinary statutory Year 6 Pie Charts content.
Dedicated pie renderer
custom-piecharts.js owns the mathematical model and SVG/PDF renderer for pie questions. It supports:
- exact sectors generated from one canonical count/proportion model;
- direct sector labels plus a legend;
- fraction, percentage and central-angle annotations;
- linked tables and answer tables;
- two-pie comparison layouts;
- exact and estimate marking modes;
- pupil-state and answer-state rendering from the same data;
- large blank/partially-started circles for construction questions.
Restrained visual colour
Custom graphical questions now use a shared six-colour palette (teal, amber, blue, coral, purple and green). The change is intentionally restrained:
- single-series bar charts may distinguish categories by colour;
- multi-series charts keep a stable series colour;
- pie sectors use the same palette;
- coordinate original/image/target/mirror cues are easier to distinguish.
Colour is supplemental. Labels, axes, geometry, relative position and chart structure still carry the mathematical meaning.
Compatibility
The older direct pie_chart_angles family remains readable for saved setups/recreation, but is moved to Extension and labelled as text-only angle practice. New curriculum-facing Pie Charts work uses the visual families.
The public /tools/99-club/ page, app.js, generator.js, pdf-layout.js, simple-pdf.js, QR implementation and public CSS are unchanged from v1.20. The new scripts continue to load only on the Custom Worksheets route.