视频选集
（15/20）
3 types of rocks _ .
08:06
air pollution for kids _ .
04:58
balanced diet _ .
05:41
how do birds fly for children _ .
06:09
human sense organs _ videos for kids _ .
02:31
layers of soil for kids _ .
06:15
layers of the earth for kids _ .
08:00
light _ videos for kids _ .
03:42
living and nonliving things for kids _ .
05:43
modes of transportation _ videos for kids _ .
02:26
parts of a plant _ videos for kids _ .
02:31
parts of the body for kids _ .
07:08
phases of moon _ .
05:23
physical and chemical changes for kids _ .
05:45
planets of the solar system _ videos for kids _ .
03:41
seasons on earth _ videos for kids _ .
03:59
states of matter for kids _ .
02:22
the 3 rs for kids _ .
10:05
tooth structure for kids _ .
03:29
water pollution for kids _ .
02:48
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