Meaning ful learning is NOT about memorising information. It is about
1- Being intentional: know why you need or want to learn
2- Active construction of knowledge: explore and find out the ideas
3- Contextualisation: understand where and when the knowledge applies
4- Colaboration: working and sharing with others to reinforce the knowledge
5- Reflection: thinking about the value and quality of the knowledge
Unfortunately, at schools students hardly get all of the above. The majority of the time, all students get is information dump from teachers who just want to get through a unit of study. When there are so many students per teacher, it is not easy to teach students with different levels of ability. This is why parents must support the kids' learning at home. It is not about just doing homework. It is about putting ideas into practice.
This is why "aspirational" parents who have time for the kids generally have smart kids who can do quality stuff. Simply hard working and going to tutoring classes are not enough. They get the high marks for a while when the content is easy (primary school level), but high school level changes all that. When they need true understanding (knowledge) not just memorised information, they need meaningful learning.
Cognitive psychologists believe that true knowledge is also represented by connections between neurons in the brain than just the memory of information. This is why we remember a lot better when we make many connections to the same piece of information. The same information that is linked to many other things and necessary for many activities will be easily recalled (remember by doing/using it all the time). Meaningful learning makes knowledge sticks in the mind. There are things we cannot forget for example how to swim. Once you know how to swim you can never forget because the brain is actually wired to support swimming. You don't just remember swimming.
Parents should encourage kids to do (1), (2), (3) and (5) above. Collaboration is not always possible. This is best done through having 1-2 best friends from schools and regularly get them to come together to play and work. Look at how successful Microsoft's founders and Apple's founders are? They were little school friends working together in the home garages!