What We Built
NumPath's teacher dashboard previously showed one number per student: 7-day accuracy. A teacher looking at "Emma — 43%" has no idea whether Emma is struggling with borrowing, place value, number sense, or all three. The number is technically correct and completely unactionable.
In this post I'll walk through how we added a Knowledge Component (KC) mastery panel to the dashboard — colour-coded progress bars per skill that expand to show p_mastery %, mastery level label, and opportunity count. The backend piece is a single endpoint backed by a left-join use case. The research reason it matters is more interesting than the code.
The Design Decision
The core choice was: what data does a teacher actually need?
