The Class President believes that the size of the boobs and intelligence are inversely proportional, so she thinks Galko is living a very carefree life.
But, she changes her mind when she sees the bulletin board Galko was intensely staring at.
her grades are erratic and unstable.
علاماتها متغيرة وغير مستقرة
sind ihre Noten sprunghaft
und instabil.
pero sus calificaciones 
no son siempre buenas.
pero sus notas no son siempre buenas.
Poitrine opulente et ferme,
mais notes fluctuantes.
as suas notas são 
irregulares e instáveis.