Check on school work. Ask them to show you the test and check where their issues are. Nothing is worse than gaps being not acknowledged.
I know that homework in primary is not seen fashionable but I found it's a great way to see what they learn and also if they are not keeping up.
Time tables is a must, easy to practice with lots of apps or websites.
It also means they are already used to some work at home so when secondary school hits and they are required to do homework/revisions/pre-learning they are not totally overwhelmed.
If you can't help them, get a tutor. DD was a typical middle child in primary, often overlooked as not the top 5% but not disruptive. So her maths issues grew and grew. 1/2 year tutoring and the problems were gone.
Go and do things with them, museums, galleries, encourage additional reading to school topics.
Read to your child even when they can read on their own, discuss their books with them, take them to plays.
Use a holiday for more than staying at an AI resort.