If it doesn't impact on your job (I.e all 3 options are viable) I'd go for Option 1 if you have children in nursery, Option 3 once they get to school. I'd be surprised if you could find a nursery to allow you to pay for childcare as set out in Option 2, and as others have said, awkward for children to keep up with whether they're in or not. If you use a private nursery you'll be paying for full time care throughout the year even though you have 10wks hols.
Opition 1 if you can get it I do opition 2 with condensed hours so get paid 5 days for essentialy 4 days childcare - but have a fair bit of flexiablity in my child care - would you? Opition 3 for preschoolers not good - a good routine is better I think - -agree for school age could be good - although if at all possible you want to be fit a coupel of drop offs and pick up in my view -
I'm just thinking of my options when I return back to work as I want to spend more time with my pre-school kids. What do you think will be better out of these 3 options (still need to get employer to agree)
Option 1) 4 day week Option 2) 1 day off every 2 weeks (say Friday) Option 3) 10 weeks holiday/yr which would be taken every 3 months in blocks of 2 - 3 weeks