K–5 · Common Core aligned · 189 words · free and open
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An open educational resource for elementary math vocabulary.
A vocabulary bank of 189 math words drawn from every Common Core domain across Kindergarten through Grade 5, with a child-facing definition, a worked example and the misconception teachers most often see for each term.
This site collects no data at all. There is no sign-in, no analytics, no cookies, no advertising, and no tracking of any kind. Nothing about you or your students is sent anywhere or stored on any server.
The only things kept are on your own device, in this browser: which words you have opened, and whether sound is on. Clearing your browser data erases them.
Every part of this tool — the word bank, the readability checks and the code — is public, so educators can see exactly how it was built, reuse it, or adapt it for their own district.
Licence — CC BY-NC 4.0. Released as an Open Educational Resource under the Creative Commons Attribution-NonCommercial 4.0 International licence. You are free to share and adapt this material for non-commercial purposes, as long as you give appropriate credit.