The only other thing I can think of is an evening job then when the kiddies are on school hols it's easier to deal with.
If you didn't need to earn so much I'd say give Avon a go, it's hard work but will fit in around children & as long as you're organised it can work for you, my daughter used to earn about £150 per month which is a nice amount but not enough for you!!!
Some cleaning jobs (not sure what area you work in), start early morning & you'd be back to get to school, would this type of thing fit in?