Frenglish: colour blind

I live in the "quartier des lycées" in Annecy, 

which means there are several big high schools just down the street.

Now that school is back in session, 

there are tons of teenagers in my neighbourhood,

riding their bikes to class,

sitting in cafés on their lunch break

& generally hanging out.

The other day, I had to laugh when I saw this boy's bookbag.

You don't get it either, huh?