To think I can WFH 9-5 in the holidays with my kids at home

You're being unreasonable.

That is not adequate care and stimulation for your children, and it's certainly not the full time commitment your employer hired and pays you for.

If you can get DH to cover a couple of days and you can use some annual leave too, I actually think it will probably be perfectly manageable - especially if you can split the days so that they're not with you while work for more than two days in a row.

You say they're happy to mostly play in their rooms all day and if you organise lunchboxes with their daily allowance of snacks, I'm sure they'll be fine.

It may not be ideal but neither is making children miserable by sending them to holiday clubs all day.

There is a difference between an hour or so a day (which could apply with the holiday clubs) or when a child is unable to go to school through illness, and what you were originally proposing OP.

The suggestions that involve a couple of days leave seem appropriate.

So long as they don't need any attention you will be fine.

Can’t you book half days off, this way you won’t use as much of your leave allowance and you can spend time with the kids in the school holidays.

I think it's very unprofessional and it also depends on the industry you work in and the nature of your role. As others say it is very demoralising for other staff who have clearly made proper childcare arrangements. I work in retail and many of our Head Office support staff work from home these days and it is a nightmare trying to get hold of them, get a response or any other form of support ... I guess they may all be totally flakey and unhelpful but there is a noticeable difference between the support we got before WFH became the norm and since. And having to have training sessions on a Computer in a busy shop when the 'trainers' are working from their comfortable homes with children, pets etc clearly in view is not very motivating. And don't get me started on the 'here's baby Betsy, she just wants to say hello before the session starts' .
There was a thread on here recently (since deleted) about a recruiter who WFH and assumed she could care for her baby at the same time ... imagine being that person looking for a job and knowing that the recruiter is not giving you their full attention. (Or for the employer 'paying' for the service').

You know your children and your job. It really depends on whether you can work effectively, if not it might get very stressful for you. If your children are fairly self sufficient I think it's good for them to entertain themselves. This thing of having to be constantly supervised and entertained by adults is new - it's normal for children to be at home doing their thing while mum does the cleaning, cooking, gardening, looks after a baby, etc. This is no different really. As long as screen time is kept at a reasonable level and the children get along it's fine. They can read books, play in the garden, do some drawing, colouring, activity books, you could put up a tent for them to play in, a few garden toys like swing ball or croquet. For maybe 2 days a week it could be a good solution, then maybe arrange some reciprocal childcare with their friends parents or resort to the occasional holiday club

I would look into local colleges that have childcare courses. So many will love to earn some extra cash looking after them and can take them to the park etc.

So if for example you did 6-8am. Had childcare 10-2pm (and worked) and then worked 6-8pm that's your wok day.

You could even propose you work 4-8pm and do a condensed week of your boss agrees it.

I think really though the answer is what will your boss know? Will having them home affect your work - eg teams meetings. Are your work hours set as in you need to sign in and out over a certain 8 hour period minus your lunch break (I know you said they are flexible but in what way?)

I work set hours a week and have flexibility in being able to leave early occasionally and work longer days other days. And I work in a school so I'm onsite for my work.

YABU on the grounds that on the days you are "W"FH, you'd be a poor employee and a poor parent.

I do it for odd days here and there, but for a full week or two or holidays that's too much.

For a couple of days in the hols that sounds fine to me. They are safe and fed and can play with each other. I started doing this on occasion but only since DC turned 9. before that he wasn't self sufficient enough to not need eyes on him and I wouldn't therefore have been able to work properly. You'll know yourself if it is workable.

There’s no way I could do this with my 6 year old. She still needs a fair amount of attention. She’d also be really grumpy if she was stuck in the house all day, she needs to burn off energy. A 9 year old would be different, but they’d still be better off at a club. Try some different holiday clubs, they’ll find one they like in the end.

I think it’s fine for a day here and there, maybe one day a week? My kids are 9 and 11 and the most we wfh without childcare is 2 days a week. They are mostly on devices so too often isn’t good. I do try to take them out for a couple of hours which I can do around work. Kids like having time at home to chill. It can feel like a waste of annual leave if they’re good at entertaining themselves!

Exactly
You are paid to work.
If you worked in an office you would have childcare and travel expenses.
I've managed people like you and NO it doesn't always work out that you only need to get children their lunch.

Where I live the local private schools often did an excellent holiday club
you could drop of between 8 -10 and collect from 4 -6. During these times it was just chilling watching some tv reading and breakfast / light snacks
10 am sharp the holiday club would start and
they used the schools private sports facilities so my DS did loads of stuff he wouldn’t normally do
you could pay extra for them to do awards like swimming badges

this was a long time ago but it wasn’t that expensive 25 a day so relative cost for that time

i hate it if I ring a business and they and they keep getting interrupted by kids
although 1 did have his dog barking in the background 😂

I think it's doable from work perspective. 6 is on the younger side to entertain themselves for so long and two of them would be bored. I would try to organise them to be away from the house half of your work days. Friends, family, club.

How irresponsible! If I were your employer I would insist that you are either full-time in the office, or you look for another job. When you are working, the job needs to have 100% of your attention - which won't happen with kids in the house. Just sort out proper childcare, like everyone else does.

For a couple of days I think it’s manageable although your employer may need to know. Mine wouldn’t be that fussed. When you know you have a meeting, prepare beforehand make sure the kids know you’re going into a meeting and mustn’t be disturbed unless an emergency. Give them a drink, snack and an activity to keep them quiet for an hour.

Mine are 8 and 10 and it works fine for them. I take a bit of annual leave, my husband takes a bit and the other days he WFH with them.
They love it. Usually mix up playing in the garden, doing a bit of their school work or reading to break up the day and then tv/consoles as well.

Mine are quite independent though and also enjoy each others company so that makes it a lot easier.

I think it’s fine for a couple of days during the holiday, me and DH do the same with DS2 and DS5. One of us starts earlier and finishes earlier whilst the other starts later and finishes later. Between that and splitting our lunchtimes the kids aren’t alone for too long. I wouldn’t do it for the whole holiday though.

I think this can be a problem, and I'm just going to echo pp saying yabu.
I've had a couple on online meetings where people have been interrupted by small children and it's not great. I'm questioning how well you can work in these circumstances and honestly some of this wfh sounds a bit slack.

My 10 yo hates holiday club , 6 weeks holidays I arrange 1 week at Grandparents 2 weeks on our annual summer holiday and 1 week summer camp. The rest of the time she's home with DH who WFH. Term time she walks home from school at 3.30 then entertains herself until DH finishes WFH a few times a week. I wouldn't feel comfortable with a 6 year old having no supervision or needing to be supervised by the sibling. It's only last term DD has stopped going breakfast, after school club and holiday club. If DH had to stop WFH I would put her back into club until secondary starts.

I think it also depends on the child, my 9 year old would be happy to sit on his switch and not move.

Can you work at the weekend in the holidays? That way, their DF can look after them whilst youre working.
The alternative would be to take parental leave, which would be unpaid. But no, you cant have them unsupervised all day.

You need to talk to your manager (and check your contract) about their policy for working at home with the children there.

Apart from you being distracted from your work (you will be), what if something happens like one of them trips over or falls down the stairs while you're on a work call? Would you sue them? Or could they sue you?

It's really unprofessional to be honest. Pay for childcare, even if it's not a club.