So just what should your kids be watching, and how much is time in front of the box is too much?
What can kids gain from TV?
TV has been blamed for everything from obesity and aggression to poor communication skills, but Clare Bolton, manager of The Talk To Your Baby campaign, run by the National Literacy Trust, is a firm believer that in the right circumstances TV is not necessarily harmful to kids.
'Singing familiar songs and responding to the same funny bits each time can help with language and understanding,' she says. 'Even better is to talk to Mum or Dad about what is going on.'
And for older children, TV often explores controversial or sensitive issues, teaching important values and helping develop critical thinking about society and the world.
What should they watch?
High-quality educational programmes that have been designed for your child's age-group are best.
'A number of high-quality programmes have been made specifically for young children and these are excellent because the producers often draw on research into young children's development in their design,' says Professor Jackie Marsh from the University of Sheffield. 'In the Night Garden is great for young children because it promotes learning and engagement - and is fun to watch.'
Clare Bolton recommends under-twos should watch less over-stimulating visual programmes, and preferably those involving a single, adult speaker.
Videos can be better than television as the repetition and familiarity of words and phrases makes it easier for children to learn from them. Your child will benefit more from this than from watching new material every time.
'The main thing is to stop TV watching being passive - responding to the screen and talking with someone about what's going on can support general conversation skills,' says Clare.
How much is too much?
Too much television can affect your child's ability to talk, listen and concentrate. Watching TV involves one-way communication - your child can 'switch off' from what they are viewing. Two-way communication, on the other hand, where your child is interacting with somebody, requires them to listen and express themselves and helps develop their communication and social skills.
Clare Bolton says: 'Unmediated television for very young children isn't great, especially for under-threes who watch more than half an hour a day. Children don't learn to speak solely by watching other people talk. They need eye contact and a chance to babble back.'
For 3-5 year olds, the National Literacy Trust recommend no more than one hour a day viewing time, although some early years professionals do recommend less.
If turning off the TV leads to tantrums, suggest fun alternatives like playing a board game, hide and seek, playing outside, reading - anything that enables you to enjoy quality time with your kids. Turn off the TV during meals and don't allow your child to watch while doing their homework. Treat TV as a privilege that kids need to earn - not a right.
How can you help learning?
Your child will benefit most from TV if they talk about what they've watched. Where possible, try to watch programmes with your child. Select shows you both enjoy, as shared interest will naturally lead to conversation. When the programme has finished, switch off the TV and talk about what happened in the story or sing songs from the show. If your child has toys related to a programme you've watched, encourage imaginative play with these.
'Children are highly motivated by television and enjoy undertaking other related activities such as reading books and comics about the characters, which can help develop their reading skills,' says Professor Jackie Marsh.
Use TV as a springboard to talk to older kids about tricky subjects and to share your own beliefs and values. If something you don't approve of appears on the screen, use the opportunity to ask your child questions about what they think about it. Teach your kids to question and learn from what they see on TV.
What's the downside?
Being sensible about your children's viewing should mean there doesn't have to be a downside, but be aware of the following:
As well as the obvious - spending too long in front of the TV can contribute to children becoming fatter, many speech and language therapists worry about the effect of TV on children's communication skills and there is general agreement that extensive viewing can affect a child's attention-span.
Several reports have also linked aggressive behaviour in children to seeing it on TV. So be on the safe side and avoid those violent cartoons.
TV taking over?
Giving your child a TV in their room gives you less control over what they watch, increasing the likelihood of inappropriate viewing and reducing time for other activities.
Consider coming up with a weekly TV schedule the whole family agrees on. Turn off the television as soon the 'scheduled' programme is over instead of channel surfing for something else to watch. And, of course, set a good example and limit your own TV viewing.
Strike a healthy balance
So long as you divide up your child's time, providing opportunities for pretend play, socialising with friends, running around outside, as well as some TV watching, you'll be on the right track.
How much TV do your children watch and at what age?
What positives and pitfalls do you see?