These libraries focus only on 3D. You may need to combine them with other libs to suit your needs.
undefinedWebGLU - WebGL helpers
mjs - vector and matrix math library optimized for WebGL
glMatrix - "stupidly fast" matrix/vertex math library for WebGL, 0.9.4, BSD
ewgl-matrices - matrix lib for WebGL
TDL - low-level library for WebGL apps. It focuses on speed of rendering rather than ease of use
GLOW - a just-above-low-level WebGL API.
learningwebgl.com - WebGL tutorials and overviews
ThreeNodes.js - vvvv clone in WebGL