First thing is I would have kept my DC away from smart phones / iPads and gaming until they were much older and would have restricted screen time much much more than I ever did.
I'd have made reading every night a basic non negotiable requirement. Once we stopped reading them a bedtime story they switched off from reading for pleasure. Reading is so important.
I would have delayed DD starting school by a year as she is a July born and we later found out she has slow processing. She's always seemed so behind.
I'd have sent DD to a less academically pushy primary school. Her primary was basically a grammar school factory. Kids like DD were left to flounder and made to feel "thick" by the other kids.
I'd have insisted DS chose the grammar school I wanted him to go to instead of the one he wanted to go to. He actually preferred the one I wanted but all his friends were going to the other so he changed his mind. I know he would have done better if he'd stuck with the school we liked better.
I'd have sent DD to private school from Y7. It probably made no difference due to Covid lockdowns during y 7 and 8 but once I transferred her to private for start of Y9 the difference in her and the support she got was amazing.
I'd have made DS change to a non grammar sixth form instead of staying on at ten grammar. The local comp's sixth form seems to get better A level results and treats the students like adults. DS still having to wear school uniform and being given detentions for very minor infringements and is almost 19! He's so over it now.
DD's last day of school at the end of this week and DS finished sixth form two weeks ago to start study leave so I'll no longer have any at school. Feels weird. DD will hopefully start college from September.