I've spent the past 4 years homeschooling... So here are my tips/tricks of having my son 24/7 ISH
1) Don't. Arrange a time once a week for an afternoon where the kids are elsewhere for several hours. That veg time/ project time/ errand time... Whatever it is that just feels good to do on your own. There are LOTS of options available for this ranging from grandparents, to playdate exchange, to half day daycare, to halfday camps.
2) STRUCTURE!!! Plan some nothing days in, but structuring the rest is vital. Even if it's just Breakfast-Lunch = Whatever time (free play), lunch to 3pm = get out of the house time, 4-5 is movie for kids and cooking for me... OR a more detailed schedule. I'm ADHD and fairly impulsive so I scheduled 'blocks' of time so I could be impulsive in how I filled them, but they were still set blocks. Both kids and adults crave structure... Working out what yours will be will be relieving for ALL of you. ESP the school aged kiddos who have no choice 10mo a year. They FORGET how to entertain themselves because schools have rigid structure, and weekends are too short to do more than relax and head back once more into the fray! During this transition they GLOM because they're used to being told what to do every minute. But give them blocks they can count on, and they'll start filling those blocks themselves instead of trying to get home to feel like school. At breakfast you can tell the oldr kids, and the younger kids will catch on what the 'schedule of events' is going to look like.
3) outside classes, camps, sports, etc.
This is a combo of 1+2. It gives them something to count on (like swimming every morning, or practice on tues/thurs, etc. AND gives you am hour or so where you're not the one in charge. Even if your watching, or just reading in the car... It's a weight off your shoulders.
4) Enlist your minions!!! Yes. Chores with kids helping takes 3x as long. Do it anyway. Instead of 3 kids pestering you while you cook, one is shredding cheese, another is setting the table, a third is sweeping up. Make each responsible for their laundry (including the 'fun' parts of adding soap, cranking the knobs, banging the lid,lobbing into the machine). With more than one kid races are often fun. I also always play 'jumping music' while cleaning (fast paced, fun). Trade chores around. Giggle. Tickle. NEVER redo their work while they're awake (why do this if mom is going to do it anyway?).
4) Some days get cancelled and become a movie day. Everyone is beat, and modern tech means e don't have to get dressed for the theatre. So, some days, everyone needs a veg / check please! day where you eat crappy food and sit on your bum. They're OKAY! Yes, it would be bad patenting if you just always sat in front of the TV. Having a movie marathon every once in awhile? FINE.
5)Theme days. We would do a PJ day once a month. PJs at home, store, outside.. It's just something dilly to do. So is backwards day, robot day, spy day, etc. some folks go all out. I'm not that spiffy. But even half of the days schtuff is in theme? We still have a blast.
6) win/win cheats. xBox kinnect = video games for THEM and active time (for them) for me. Educational computer games. Documentaries (movies + learning = not feeling so bad about screen time).
7) Boredom breeds creativity. Kids being bored IMNSHO, is a GREAT thing!!! Their imaginations have shut off, so being bored -as long S they have to 'save themselves' gets their imaginations up and running again. I often combined this with a 'no electronics' day or week.
8) Bad behavior (ESP fighting) means they're banished from good society. Not just timeout, but a good solid hour or more by themselves in their rooms. If you want to be around me or other people... That means treating us with respect. <grin> This happens 2-3 times a year in my house. Kiddo gets obnoxious and I cancel everything for the morning or afternoon and he spends it in his room while I read a book, watch a movie, etc. if its just us. If its 3 or more (I usually take the cousins a few weeks every summer), then it's normal life for the rest of us while the fighters spend a couple hours in their rooms. Separated.
So NOT a complete list, just some things that have worked in my life.