Starve them out op! 😃
Seriously though you usually have to use guile. I use more straightforward enforcement of routines during term time but during holidays a more subtle approach works better.
The worst thing you can do is the direct approach eg “everyone up now!”
Or hang around waiting for them.
Get on with your own stuff and they will sidle down and maybe join in.
Start baking, painting a wall, playing table tennis with your dh on the kitchen table, a diy project … .
Model the behaviour you want them to do: bicycling, sport, gym, trying new things. Teens hate a hypocrite! And make no mistake they are watching you and your daily habits even though they appear to be shut off. (You need to get your dh on side here.)
Or, get each of them to decide individually on a day out of their choosing during the holidays (according to a budget) with the agreement that they all have to attend each others or no one goes anywhere. That way they urge each other to get up and out.
Sometimes it works to rush in to their rooms wearing a coat looking busy and mention that you are driving past the shops on your way to somewhere else and does anyone need dropping off and collecting? And once you have them captive in the car, go on a detour via a skate park, climbing wall, IKEA, sculpture park and reward with junk food on way home, end on a positive note. My older teen and I actually shared a quick complicit smile when I played the “oh look, what a surprise, we’ve ended up here!” trick on her younger cousin recently. 😄
A few of them won’t want to come with you initially but they’ll start to hear from others what you did and will maybe venture out next time.
Maybe introduce an animal in to your life and if it’s a dog get a walking rota going. It’s much easier to enforce good animal welfare standards than tidying their rooms. Love is a verb etc.
Invite some other people around to the house to change the dynamic. Or put on loud music.
Pretend you need help with something - video, phone, carrying heavy furniture, helping an elderly neighbour, navigating the route to an errand, and entice them out that way.
Finally, bribery. Send them off supermarket shopping and tell them they can keep the change (a set amount) that you will be back in a couple of hours and that they are cooking tonight. (Persuade your dh out of the house for this one.) Or set them a serious adult problem to solve (the door on the landing that sticks) it’s surprisingly what they can achieve when left to their own devices.
I have also done the “I am half way through prep of lunch or dinner”
trick “and I have to go and drop x off urgently , can you
please take over and I will be back soon?” then take your dh out for a quiet drink.
Or just leave your older two in charge of the younger ones and take your dh out for the entire day. They will survive! You might be surprised what they get up to!
Finally, if all else fails, turn off the Wi-fi for a couple of hours late morning or early afternoon. My experience is that teens enjoy lying in until late morning but after that everyone gets a bit grouchy and restless. They need something concrete to do every other day at least. I work on the rough agreement that we alternate between one day free for themselves and one day doing something together or individually.
And get a time tracking app on their phones that they have to report in about every so often. You can write the hours up
on a chalk board if you want and reward a prize for fewest hours on line. No lectures or comment. Just leave it up for everyone to see!
Remember though that while being on your phone does tend to lead to a lack of physical activity which definitely needs addressing ; it doesn’t necessarily equate with zero other activities.
In my day we had phones to chat our friends, Walkmans to play music, books to read, tape recorders to learn stuff off by heart, drawing materials to practice art, encyclopaedias from which to learn, a diary to write in etc … and one phone can serve all of those purposes in one. So your teens might not be as inactive as you think they are!