that most children spend more than an hour a day on this type of activity.
Time for a new schedule
Too much TV can clearly damage school performance. And if we are to take the transition from no school to school as seriously as the transition from primary to secondary, then schools have a responsibility to talk to parents about this when they enrol their children.
One practical suggestion is monitoring. It is one of the simplest ways to make sure that children spend an appropriate amount of time using electronic media. Some parents keep a simple diary on their fridge - with the child's name down the left-hand side and times across the top. It is easy to fill in - just mark which child was using electronic media for which period of the day. Doing this over a couple of days and adding up the hours can be eye-opening. When my team advises parents to do this, many find that their children are spending about twice as much time using electronic media as they thought they were.
It is also important to look at why parents let children watch so much TV in the first place. Many need to keep children safely occupied while they attend to various responsibilities - this is one of parenting's great challenges. TV is often viewed as a great babysitter because it will hold children's attention for a sustained period of time. In reality, other pastimes can just be as effective - for example, reading a book, playing with blocks, a train set or a favourite toy, or doing craft activities.
Admittedly, cutting down on TV time is not always easy. Schools need to let parents know that changing a child's behaviour will not be a quick process. It will take persistence, and possibly a few unpleasant tantrums, to alter their habits. But many parents find that applying the new rules consistently can bring about change fairly quickly - often within a few days.
Teachers, too, may feel that this is a lot of work to cram into an already heavy busy schedule, but the relevant information can be presented easily enough in welcome packs when children's names are put down for a school, and perhaps in welcome meetings, too.
It should also be seen as an opportunity. Schools can set out a framework of activities and resources that will not only provide an alternative to electronic media but also develop the skills and knowledge that prepare a child for school. This will ease the initial transition period and enable pupils to make better progress once they arrive.
It is important to note that I am not advocating turning off the television completely. Everything has its place and a little bit of high-quality programming is not going to leave a child lagging behind when school starts. But inappropriate viewing and watching too much is likely to have an impact.
So educators have an important role to play in informing and supporting parents on this topic. Many parents are unaware of the possible risks for their children and do not have access to the evidence. Schools can act as a conduit for information, leading to considerable benefits for all involved.
Trina Hinkley is a researcher in the Faculty of Health at Deakin University, Australia