Courtney Heina, age 9, of Winston Salem, North Carolina, for his question:

Where does the water go when the tide goes out?

When the tide on your favorite beach goes out, the great ocean piles up high water along other shores. The high tides and. low tides chase each other around and around the globe. This rocks the waters of the world wide ocean up and down on different sides of the globe. Every calendar day, a high tide and low tide chase another high and low tide around the world. You might think that people on the far side of the world get low tides when you do. But this is not so because the two high and two low tides devide the globe into quarter sections.

Halfway around the world, the beaches on the opposite side of the globe get low tide when you do. The high water piles up midway between the low tides. It brings high tides to the shores a quarter of the way around the globe. Every calendar day, the vast ocean heaves up two tides of high water and swings them clear around the globe. And the two great troughs of low tide water between them bring the low tides.