This spurt of growth in girls usually begins two years earlier than in boys, and their growth rate is somewhat less than that of boys. Most people stop growing some time between the ages of 18 and 30. A person is usually tallest about the age of 20. When a person stops growing in height, he begins to shrink due to a thinning of the pads of cartilage that grow between the bones of the backbone. Fruit Fly Metamorphosis.
Insects develop through a series of stages.
Each stage has a form very different from the others. Metamorphosis is development by radical change. Have students place a piece of a ripe banana in an open quart jar and leave it in a warm place for several days. If fruit flies are around, you will soon see them flying in the jar. You can purchase fruit flies from a biological supply company if you prefer.