Think of your list as an inverted pyramid. At the top (the widest part) are tasks that need to get done, but aren't as urgent, such as preparing for your children's activities. At the bottom of the pyramid (the tip) are the tasks most important. The problem that arises is things at the bottom of the pyramid are not completed because too much time is spent on the least important to-dos and, thus, taking up more space in your brain as well as more energy. When the pyramid inverts, you become less productive.
With all these great tips on how to make your to-do list more manageable, what are you waiting for? Get to work!