Preschoolers count objects most accurately when they gesture as they count.
This study tests two possible explanations for this effect. One is that ge
sture helps children keep track of counted items. Another is that gesture h
elps children coordinate saying the number words and tagging the items. Twe
nty preschoolers counted chips under three types of conditions: with gestur
e prohibited, with active gesture, and with a puppet gesturing as children
counted aloud. The puppet conditions were intended to distinguish the benef
its of keeping track with gesture from the benefits of active gesture. Chil
dren counted more accurately when they or the puppet gestured than when ges
ture was prohibited. However, children's errors differed when they and the
puppet gestured. When children gestured themselves, they made errors keepin
g track, but when the puppet gestured, they made errors coordinating number
words and items. Thus, active gesture helps children both to keep track an
d to coordinate tagging the items and saying the number words. In these way
s, active gesture helps children implement their knowledge of one-to-one co
rrespondence.