Cup stacking is a sport in which participants stack and un-stack specially designed plastic cups in pre-determined sequences. Preliminary research, although limited, has found some support for claims made by the manufacturer that the activity improves coordination by improving ambidexterity, developing hand-eye accuracy, and promoting upper extremity quickness (Speed Stacks, Inc., 2005). Many physical educators have started cup stacking programs in their schools, however, little research has been conducted to examine how best to address practice structure for this activity. The purpose of this study was to test two separate techniques of practice on cup stacking performance. Thirty volunteer participants ranging between 19-27 years old, all of whom had no prior training or experience in cup stacking, were randomly assigned to the massed (n=10), distributed (n=10), and control (n=10) practice sessions. The massed group practiced a series of stacking sequences for 60 consecutive minutes. The distributed group, practiced for three 20-minute sessions. The control group did not practice cup-stacking. All groups were pre- and post-tested on reaction time (RT), using the same Yardstick test as reported by Udermann, Mayer, Murray and Sagerdorf (2004). RT data were analyzed using a 3 (Group) x 2 (Test) mixed ANOVA. There was a significant interaction (Group x Test), F(2,27)=8.910, p<.05). LSD post hoc analyses revealed that only the massed and distributed groups improved their reaction times following the 1-hour cup stacking practice. Cup stacking performance between these two groups was compared by examination of stacking time for three sequences (6; 3-6-3 and 6-6) with the latter sequence serving as a transfer test. A 2 (Group) by 3 (Sequence) mixed ANOVA was used. There was a significant Group main effect (F(1,18)=9.318, p<.05) with faster stacking times exhibited for the distributed group. There was no significant Group x Sequence interaction, F(2,36)=.33, p>.05. It was concluded that practicing cup stacking in a distributed fashion will lead to better performance, however reaction time gains can be elicited with either practice schedule after only one hour of practice.Keyword(s): motor skills