Put your kids to bed at a reasonable time. They need more sleep than you do, and they need to perform, in school or pre-school, better than you probably do at work. Letting them stay up late, while it might help you the next day, hinders them; they need a consistent schedule.
My guess is, you might want to keep them up at night, so they sleep late the next day. Wrong answer. It is your responsibility to give them a consistent, health-giving environment. So, you've got to buck up. You then have a choice: a) you get less "along time" after they go to bed, or b) you have to drink more coffee when they drag your lazy selfish asses out of bed earlier than you want to get up on a Saturday or Sunday morning. Deal with it. Buy a coffee pot with a timer.
The patterns you set for these kids will be with them for a long time.