Well detailed discussion of the use of the couplet in poetry. A number of different kinds of couplets are defined and explained (short couplet, split couplet, heroic couplet, Alexandrine couplet, Qasida), and a "How To" section suggests...

With craft and recycled materials, kids can make all kinds of rolling vehicles. Add balloons to make this balloon car and see Newton's laws of motion in action.