The study was designed to compare the scaffolding skills of Korean teachers identified as developmentally appropriate practice (DAP) or inappropriate practice (DIP) in their beliefs before and after an in-service training experience. Based on DAP beliefs of 242 kindergarten teachers, 30 DAP and 30 DIP teachers were selected. Thirty (15 DAP, 15 DIP) kindergarten teachers attended the training program while 30 (15 DAP, 15 DIP) comparison kindergarten teachers did not. Before the training, there was no significant difference between DAP teachers' scaffolding and DIP teachers' scaffolding. However, DAP teachers made significantly greater gains on a scaffolding measure than DIP teachers after teacher training which provided scaffolding skills and strategies.