Earlier this year I sent a polite email to parents to gauge the level of computer and internet access my students had outside school. The following reply wasn't unique, but it was telling:

Dear Mr Cohen, xxxxxxxxxx has their own computer and access to the internet ...time on the computer is deliberately limited for xxxxxxxxxx because their game playing became excessive.

This situation is something most parents have to deal with in one form or another. It used to be so obvious when kids were spending too much time playing games or goofing off online - the house's only computer or TV was being monopolised for hours on end. Tech is cheaper now, and it's in their rooms, in their hands, and often out of sight. What's a caring parent to do?

Fortunately, there are plenty of free or cheap options available if you want to manage your kid's digital tomfoolery in a way that is both effective and respectful. We'll break these down into the three main categories of distraction; consoles, online, and mobile.

Consoles

This is the area most familiar to modern parents - if you didn't lose a few hours to Mario or Sonic in your youth chances are you won't be reading this anyway. But the computing power of modern consoles, coupled with gameplay built on three decades of studying player behaviour, has combined to create games designed to be deeply immersive and a little addictive. So, how to keep tabs on the epic time-sink that is console gaming?

The good news is the 'big three' console makers have included parental controls that help you make decisions about the kind of games you want your kids to be playing. Sony's and Nintendo's allow you to control internet access and manage games based on their rating (although Sony's numbered 1-11 system is weird - head to the user agreement for an explanation).

Microsoft has gone a big step further. The Xbox Parental Controls allow you to place daily or weekly time limits on how long a given user can play on the console - they even get warnings to save their progress when time is low. This system allows control but also incentives; you can put more time on their account ad hoc, perhaps as a reward for finishing homework or just to get in a game of Lego Harry Potter with them before bed.

Online

First off, do not let the kids have admin privileges on the family computer. This means that they will have to involve you to install programs or add-ons, so you can keep track of what they're doing. Added bonus - you are now actively talking to your children about their computing habits!

Also, let's assume your kids know how to use private browsing. If you're a Mac user you can disable this at the account level, for the rest of us there's the recently-released Incognito Gone. This free program removes the privacy mode from whatever browser you install it on. It's worth noting that installing the program is a permanent change to the browser, but you didn't have anything to hide, did you?

Now everything's out in the open, I cannot stress enough how important it is to involve your children in the decision-making about which sites to limit access to. Kids are aware that they let themselves get distracted and will probably find a management solution that doesn't feel like a ban-hammer to be fair, or at least reasonable.

Finally, use your admin privileges to install either LeechBlock for Firefox or Nanny for Chrome. The beauty of these add-ons is that you don't just select the sites to be blocked, you can select when they are to be blocked. So you can stop Facebook access until you get home from work, or limit game websites to weekends, or... you get the idea. Blanket bans can also be enforced and removed quickly and easily.

Mobile

The number of handheld electronic devices available to young people is unprecedented. I have vague recollections of borrowing a friend's Gameboy for 24 hours and having to treat it like it was made out of pure Unobtainium. Now the biggest choice a parent has to face is whether the next gaming device they buy for their child is also a phone.

The two big players in dedicated portable game consoles (Nintendo and Sony), have parental control systems that are basically a straight port from the Wii and PS3, so make the necessary adjustments regarding ratings levels and (if you want to) turn off the web browsers.

Now for Apple devices. You want absolute power? Start by heading into the Restrictions menu (Settings > General > Restrictions) and setting a passcode. You can then limit anything from whether the camera works to whether you can make in-app purchases. Bear in mind that your child will probably be expecting an unfettered iExperience and will be highly indignant if you drop this on them without explaining your reasons. Again, communication is the key.

Also, if your child has an iDevice you've probably already set them up an iTunes account. Giving them iTunes vouchers are a great way to keep track of their spending, but you can also automate payments to their account using the 'Allowance' feature. Try matching this with enabling in-app spending for some free lessons on money management!

I hope you've noticed the thread running through this article: talk to your kids about how they are spending their time - if they used all their iTunes credit buying in-game items, have a chat with them about Skinner Boxes. Better yet, if they just spent a whole weekend playing a new game, demand a first-level walkthrough.

Or just drag your old N64 out and school them, Mario-Kart style.