PNG ICO ICNS MORE
Mixed
Smooth
Simplicio
school, Manage
SteelBlue
128x128
Business & finance
Sigma
student, school, Elementary
Black
400x400
Music & multimedia
Soft Icons
school, read, dictionary
WhiteSmoke
Black board, math, school
SeaGreen
Network & communications
Oxygen
Blackboard, calculate, school
DarkSeaGreen