As a day care mom, I used to leave work to pick up my children before day care closes at 6pm (until we had three kids, hired an au pair and then I left work at 5:30 to meet her at home by 6 after she picked everyone up). Over the last eight years, 5:30 - 7:30 pm has become sacred time. Without spending it with my kids, I get stressed and our lives get crazy.
5:30 because day care closes and after school activities end.
7:30 because it's bedtime so that my kids get the 11-12 hours they need per night to be energetic and well behaved at school, day care or camp the next day. Basically, so they're fun to be with rather than whiney, cranky monsters.
I've changed jobs every time I got pregnant and one-time, twice. And since my third most recent change (three kids, four changes), I've discussed my family time schedule with prospective hiring managers in my interviews. To their credit, they each told me that they would respect it and they each did.
It's ingrained in my schedule and that of my family and my colleagues. I recommend it to every parent. Because I do it 7 days a week, it's easy to plan on it. The kids know they are going to have time to talk, cuddle and play with me. Homework is checked and piano is practiced. The cell phone is off. The blackberry is charging. People don't call (except in emergencies). For 90-120 minutes per day, they have my full attention (other than cooking, bathing, reading - the normal chaos that goes into the witching hour).
My routine is not unusual - studies indicate children are getting daily time with their working parents. I figure - no one dies if I don't answer an email for 2 hours. And I reap the benefits because I need those cuddles and visits as much as they do - best stress reliever in the world.