The Scottish painter James Cowie (1886-1956) also worked as a teacher, and portrayed many of his students.
The sketches he did beforehand, in pencil and watercolor, are beautiful also, just look at the boy in the middle of the top row, and the to girls on the right.
My favorite Cowie painting has to be 'The two schoolgirls', top left.
What is it they are holding? Are they smocks, to put on when they themselves will paint?
Maybe it's their needlework?
The girls look a bit nonplussed, as if they don't understand why someone would want to paint them.
The lady with the yellow glove however, is posing very confidently.