Relax and laugh with your children. Children benefit from seeing adults use humor in a positive way. Instead of yelling, have a race to see who gets dressed in the quickest time. The winner gets to choose desert at dinner. Comment on how amazing it is that your family could oversleep and yet get out the door in such a short amount of time.
Studies show that optimists have a higher level of self-confidence.
Encourage positive risk taking. Self confident children have the inner fortitude to try new things even if it means a chance of failure. Encourage your children to try out for the school play or enter an art contest. As a family, read a book together on a subject new to all of you. Take a fall bike ride on an unfamiliar path, even if you don't know where you'll end up.