B.B.
I don't know how old your older two boys are, but here are some options in the winter (I have always been a stay at home mom. Now my kids are 5, 8, 10 and 11). The library is good - look at books, read books to them, and sometimes they have scheduled story times or other activities, often free. Same goes for Borders and Barnes & Noble - scheduled story times are fun too, and often have another small activity or craft time and maybe even a cookie. One of the malls in St. Louis has a carousel for a small fee. I'd go and tell them we get two rides. Of course there's the usual science center, kids' museum, etc., but you can't do those everyday. How about art supplies - construction paper, glue, paint, whatever, head to Michael's or even the school supplies aisle of Target and you may get some ideas to keep everyone happy. You could also check out a book at the library about science experiments if they're into that. Simple stuff you could do at home.
As for juggling - I have a hard time with that. There's always, always, always laundry to do. I'm NEVER EVER caught up with it and someone is always out of pants, underwear or whatever. I try to keep up with cleaning, but that's hard and I try to cook dinner when it's not dinner time so that I'm not in a rush when 5:00 comes and I have absolutely no idea what we will be eating in an hour. I do let them watch tv, play electronics - that's my time to do the other stuff. To be honest, I'm not entertaining them 24 hours a day, but we do our best. Have a friend over with kids, have their friends over and you'll be reciprocated too. My house is cluttered, and not the cleanest, but I like to think it's a happy home. It'll be an adjustment, have fun. Happy Holidays.