I think she feels a bit lost now that the kids are getting older. She's missing a structure and a purpose in her daily life. Something she probably found in her garden in their house before.
Everyone else in the family is settled with a job or school, they have daily contacts with colleagues or classmates. The kids have their friends that they see after school. And Fern is just trying to fill her days with meaningless activities and she knows it. She's not happy and probably lonely, you can tell... Especially when she mentioned, she would love to take the kids out of school so they could learn from life.
That's more for her benefit than for the kids, to stop her feeling lonely and make her feel wanted.
But I don't think the kids are up for that, except maybe if they could game all day, watch tiktoks and go shopping. A lot of kids wouldn't mind that
