62 TEACHING SCIENCE IN THE ELEMENTARY SCHOOL

and temperature affect us and how we regulate and control
some conditions of weather.
 One of these activities is a collection or a list of ther-
 mometers, such as the oven thermometer, icebox thermometer,
 candy or icing thermometer, clinical thermometer, automobile
 thermometer. The children know from home experience that
 mother's cake burns when the oven is too hot and that their
 candy often fails to harden because their candy thermometer is
 broken and they cannot test for temperature of the cooking in-
 gredients. They see that it is often very desirable to measure
 and control heat.
 Johnny has noticed that father watches the tube or needle
 in the automobile thermometer to see if the car motor gets too
 hot. He knows that if the needle moves too far across the dial,
 the motor is too hot indicating that something has gone wrong.
 Thermometers tell us something about which it is not safe to
 guess (a lead into safety).
 As other types of thermometers are brought in or discussed,
 it is noticed that the numbers on these are different, have dif-
 ferent meanings, and that the instruments themselves are dif-
 ferent (a lead into arithmetic).
 For the more mature groups, thermometer models may be
 made with movable tape which can be adjusted by hand for the
 purpose of recording and comparing temperatures (more leads
 into arithmetic: measuring).
 Another activity is the making of a chart to be used for
a period of time to note the variable quality of the weather.
Class suggested symbols to indicate the kinds of weather each
day make the keeping of this record easy and interesting (a lead
into study of the days and months).
 Many learning about weather conditions and how they
effect plants and animals grow out of observation. On a walk
during a hot day we see plants that are withered and curled in-
dicating their need of moisture and their way of protecting them-
selves. On the same day Johnnie's cat is apt to be in the shade
of the hedge. Plants and animals adapt themselves to intense
heat.
 On the first cool morning in fall, coats and sweaters appear
for the first time during the school year. Children examine
and admire the new apparel of their friends. Perhaps for the
first time in their lives they hear this important event spoken
of as a way in which people prepare for winter ( a lead into
social studies).

D. Experiments
 1. Through questions children often raise problems that can be suc-
 cessfully solved by experimentation. "Is there water in the air?"