If you’re concerned that your child is not bringing enough homework, you can ask them to use BBC Bitesize. Every subject on the U.K. curriculum is there. They can revise or practice some questions.
There are many other resources which are specific to the different specifications but this one tries to capture the basic concepts for each subject. It should be used in conjunction with other resources.
Talk to their teachers and ask them what online resources your child can use at home. Show interest in your child’s education.