It is the role of a parent to encourage a good ethic for study early on in a child's schooling. As your child grows into adolescence they might not prioritize their home learning and study time, as many more interesting things (to them) can take up their full attention. Fear not, as a parent there are many small things that can be done to help nudge them in the right direction and establish some kind of routine for study time at home.
First, setting the scene for study time is important. Dedicate a quiet and clutter-free place in the home that can be used for homework. This needn't be an office or even at a desk - a dedicated time sat at the kitchen table is just as ideal. Establishing a time and place for study is good practice, and will establish the routine that is needed to help your child develop the study habit. Good overhead lighting, comfortable seating, and no distractions such as cell phones or having the TV on will also help.
Encourage your child to make a study timetable. This is something that can be done together as parent and child, and lots of resources to help with this can be found online. You can work out what is a priority and help distribute their time and focus effectively.
Never underestimate the effect that good nutrition and a good nights sleep will have on your teenager's brain function. Establishing positive routines such as eating a proper breakfast every morning, drinking enough water, and having a regular bedtime are all factors that will contribute towards them being able to study well.
It is said that twenty minutes is the optimum concentration time for both teenagers and adults. Therefore, to prevent their mind wandering and boredom setting in, and to help them get the most out of their time at the books, allow small breaks and help break their study into chunks of valuable time. Also as a parent, it is a good idea to be present at times to give encouragement and praise to your child.
It is important to remember that you cannot do the studying for your child; there is only so much you can do. But, your role as a parent is vital and it is your job to support them as much as possible. By establishing the routines and habits mentioned here you are setting your teen up for a positive period of studying and learning which will set them up for not only their approaching tests, but set them in good stead for life long learning.