I have three kids and spend about 1,000 a month on groceries give or take (this includes diapers and household stuff whatever I buy in a grocery store). It can be $800 some months and $1,200 others. Depending on if I'm hosting guests for Shabbos and how many shabbosim in the month. I don't go grocery shopping much. The less I go to the store the easier it is to keep to my budget. I try to only shop once a week before Shabbos. I cook a lot for Shabbos and eat leftovers through Tuesday. Wednesday and Thursday we will have fresh supper. if my kids dont like supper they can have pasta and salad or an omelet instead. I live in Israel and I think it is much easier to live on less here. My kids don't feel deprived in any way.