Robert Plutnick, age l0, of Old Bridge, N.J., for his question:

What do tadpoles eat?

This is the season when young nature lovers take home a jar of frog eggs. The youngsters that hatch from the jellified eggs are wriggly black tadpoles, and these junior frogs are not at all like their parents. They do best in water taken from their own pond or stream  and be sure to add a few of their own water weeds.

If you change the water every few days with fresh supplies from the pond, you do not have to feed the tadpoles. Their tiny round mouths nibble the water weeds and swallow miniature scraps floating in the water. The water from an outdoor pond or stream teems with scraps and with living plants and animals too small for our eyes to see. But this microscopic debris comes in just the right bite sized pieces to feed a batch of growing tadpoles.