"What is your favorite extracurricular activity?"
It means, "Which are some of your favorite things."
Mis comidas favoritas (not favoritos) means my favorite meals, or my favorite foods.
It means "What extracurricular sports activities do you participate in?"
You say: the activities
Mis Favoritas was created on 2010-06-08.
Mis Canciones Favoritas was created in 2003-04.
It means "Activities Workbook"
"Deportes favoritas" favoritOs NOT favoritAs
Comisión de Actividades Infantiles was created in 1984.
Mis joyas favoritas.
en que consisten las actividades secundarias
The budget of Comisión Nacional de Actividades Espaciales is 148,000,000 dollars.