Teenagers should try to include a combination of aerobic activities (swimming or walking), strength training (sit ups or weight training) and flexibility training (yoga or stretching) in their exercise regime. But how much is enough? And do they need to do it daily? Here's what concerned parents need to know.

For the first time, the American Academy of Pediatrics has issued guidance on safe tattoos, piercings, and scarification for young people. They aren't saying not to get tattoos — kids still have to ask Mum or Dad about that in most places, anyway. But they have some advice if you're thinking about it.

Teenagers don't enjoy talking to their parents. Actually, scratch that. Many don't talk that much to their friends either, at least not with their voices. Teenagers like to text. Walk into any establishment where teens hang out and you will see them clumped together in small groups hovering over their cell phones. Sometimes they even text the people sitting right next to them.

It's a strange way of life.

Jolie Kerr is a cleaning expert, advice columnist and author of the New York Times bestselling book, My Boyfriend Barfed In My Handbag ... And Other Things You Can’t Ask Martha. Her flagship column, “Ask a Clean Person”, debuted in 2011. Here on Lifehacker, we’ve launched a new iteration of it, focusing on parenting and all the messes it brings.

Here’s what Kristina Kuzmic knows: Perfection is boring. Parenthood is messy. We might as well embrace the chaos. In her funny and compassionate videos, the vlogging star — who has over two million Facebook fans — slams the notion that mums and dads should be loving every minute of raising kids.

She gets real, addressing the oh-so-familiar parenting hangover, the unpredictability of teenagers, and her stance that her kids are not her friends (“If you’re 30- or 40-something, and your best friend is an eight-year-old, that’s just weird”). Kuzmic gives us a look into her daily life.

Being a teenager in 2018 — I don’t know how it’s done. Imagine having the same list of pressures that you had as a high school kid — school, extracurriculars, chores, a social life often filled with angst — and then adding on the constant pull of social media, alerting you to all the things you aren't doing. (“Did you see that Gigi is building houses in Africa this summer and that Jonah has an internship at Snapchat?”)

Dear Lifehacker, I'm a teenager in year 10 and I've started looking at things like programming and coding. I was wondering if you could tell me how to get started with programs like C and Python? I've struggled to find helpful tutorials online for teenagers.

When it comes to teens getting enough sleep, numerous forces are working against them. Early school start times are wreaking havoc on their circadian rhythms. An overload of after-school activities is turning bedtime into gotta-start-on-homework time. The buzz of texts from friends, the screens shining in their faces and the constant lure of just one more game or episode of Riverdale are keeping their brains wired well into the night. And all the lectures coming from concerned mums and dads seem to be dissolving into thin air because, well, adolescence. And so they slog through their days, cranky and short-fused and barely able to respond to basic questions. As parents, you wonder if there's anything you can do to help.

Some call it the "good kids' high." Children and teens are playing the so-called "choking game" - an activity in which they strangle themselves or friends for an instant shot of euphoria - believing it's cheaper, quicker, easier and more legal than buying booze or pot. The game, which goes by many different names, is not new, but in an age of stupid teen challenges on social media, hospitals are warning parents about it once again.

Oh, that boy. You gave him life, and now he writhes in agony every time you get jiggy with it while driving him and his buddies to footy practice. What gives?

Dear Lifehacker, I'm getting myself organised to move out of home for the very first time in a few months. I was wondering if you had tips for the kinds of things I won't realise I need until I move in? Apart from the obvious essentials (bed, fridge, etc.), what should I be buying?

The teenage years are some of the most complicated for our children. Bodily changes, hormonal swings, and new feelings all make it an important time for your child to have your support. But teens often either don’t know how to talk to you or even may not initially want to, so most of the responsibility will fall on you as a parent. Here are a few things to keep in mind when reaching out to your teen.

High school is supposed to prepare you for real life, but sometimes it falls short. If you're looking for essentials to teach your kids (or learn as an adult), here are one Stanford dean's suggestions.