I would sit down with a pen and paper (ok - younger folk than I would use a spreadsheet no doubt) and write down all the costs that you, as a family, have each month. Mortgage / rent, council tax, utilities, phone, water, childcare, etc.
Then add in all the annual costs - things like Christmas and birthday presents add up, insurances, TV Licence, MOT, holiday.
Then factor in the weekly costs - food, toiletries, cleaning stuff, petrol, bus fares, if you have lunches or coffee out, etc.
Then the 'now and then' costs - haircuts, replacing clothes, etc.
Then I'd add in at least a 15 - 20% contingency for things you may have forgotten / unexpected costs / saving up to repair or replace bigger goods such as washing machine.
This gives you a figure for your outgoings. From that, you can work out where the money is coming from, to meet these expenses.
My suggestion would be to put all money coming in to the household (your wages, his, child benefit, possibly tax credits) into the family account, and then, if you have 'spare' then you both get an equal amount of 'personal spends' per month from that.
If sitting down and plotting all the figures show you don't have enough to cover your costs, then you ask him for suggestions as to where the money is going to come from if he has an issue with you doing extra work in the evenings.