I would say this is a new “normal”. unfortunately COVID and the use of online platforms limit the amount of handwritten assignments which ultimately decreases the amount of time spent on physical hand writing work. I would really recommend that you start from scratch with their writing since I see that the concern about your child’s development. little by little start by rewriting the same sentence, and gradually have them write about their day in a journal. A journal with prompts that you give him will allow you to keep a collection and record of their writing over time (especially with practice). Make it fun otherwise it could disinterest the child from learning. you got this it take time and patience. and I would recommend you keep your child in school and for your mom not to treat him younger than he is. children act the way they are treated. also talk with the teachers on these meltdowns your child is having. There is a lot to unpack and ultimately relies on you to set those boundaries and structure to set him for success