'To take (st) for granted' is an idiom, and it can have two meanings.
1. To not appreciate something, and it usually has the flavor or usage of not appreciating something until you lost it or it was taken away from you, and now you miss it, as in "I always took those carefree days for granted." (has the tone that your days are busy and hectic now, and you never fully enjoyed or appreciated carefree days when you had them, probably talking about when you were younger.)
2. To accept something as true without questioning it. This is much less used in AmE, to the point Americans probably always associate 'to take for granted' with the first meaning.
(not a teacher, just a language lover)