Only read some of the thread, not interested in the school in the slightest.
It would be doable, but I think it would be hard, and a life constantly struggling is soooo miserable.
RENT 1000 - We pay £700 a month for a 2 bed terrace in an average-poor area, so that may be optimistic. Ours is a good rent compared to most round here (admittedly I am south rather than se... no idea what the difference is)
BILLS all 150 Gas/elec/water I assume? If all double glazed, then sure.
COUNCIL TAX 120 Could go up a bit, but ok...
POCKET MONEY dh and I 200 I want £100 pocket money a month
FUEL 100 How far will the commute be to work/school? We go through £120 a month.
KIDS EXTRA 100 Doable if you don't tend to do much in the way of clothes, activities etc.
CONTIGENCY 100 Is this emergencies or savings for birthdays/christmas too?
FOOD AND HOUSEHOLD 400 - Completely doable. We are a family of 4 and manage on about £120 a MONTH for food/household.
SCHOOL 420
Missing from the list - car tax, insurance, mot. Is home insurance on the list somewhere? You need something put by each month to cover birthdays and christmas.