Can you feel that first wave of tired, the point when sleep would come easily, sweetly, where you'd sleep through the night, and wake wonderfully refreshed, ready to take on the new day?
Is no one else needing your attention? Does your husband have bedtime under control, smoothly transitioning the tired kiddos from pj's to clean teeth and faces, to a couple stories and all the rest?
This is the time! Seize your chance now, go brush your teeth, ease quietly into bed, keep prayers simple and sweet, meditate with the lights out, let yourself drift into sweet sweet dreams...because if you wait even 10 minutes longer you may find 3 projects that don't seem too hard, possibly folding the clean laundry on the couch, catching up on facebook, and just a bit of straightening up. Then you may get a second wind, a wave of clarity, a willingness to sweep the kitchen floor, write a letter, balance the check book, finish that movie from last night that wasn't all that good but you're curious to know how it ends.
Oh, that would be sad. Because in that time of a little of this and a little of that, you might begin to think deep thoughts about your life, about your children or realize what changes would make that chocolate cake recipe perfect. Before you know it, you've got pen and paper out and you're writing a "to do" for the next day, for the next week.
Unfortunately it's getting late now. Your mind is going full steam ahead, but your body is looking at the clock, periodically counting the number of hours you'll sleep if you go to bed by x time, then y time, then z time, which won't really allow for enough rest (even if you could get your mind to relax again), though you'll be alright.
But alas, you will probably not wake with that completely refreshed feeling that was within your reach.