Kids ungrateful for Christmas gifts

My kids are very ungrateful and it's getting on my nerves! We are not well off, but we got a very nice donation from their school and they got plenty of fantastic gifts. Christmas day they were complaining that they were bored and even today they just sat around and said they are having a bad day! I'm so frustrated. They rarely get toys because we don't have much money, but they act like spoiled brats! I was never this way growing up. They are 9, 8, 7 and 5 yrs old!

What would you do? I'm going to blow up! The only one playing with their toys and having fun is my 1.5yr old and 4 month old 🙄