In this study, the effect of modeling based activities using virtual environments and concrete objects on spatial thinking and mental rotation skills was investigated. The study was designed as a pretest-posttest model with a control group, which is one of the experimental research models. The study was carried out on sixth grade students attending Maresal Mustafa Kemal Primary School in Konya's city center during the 2010-2011 academic year. The study group is composed of a total of 87 students in two experimental and one control group. In the activities applied for 9 weeks in the experimental groups, a total of 18 different models were developed. As a result of the study, it was found that the spatial thinking skills of Experimental Group, 1 in which concrete objects were used to develop models, were significantly higher compared to those in Experimental Group 2 and the Control group. The mental rotation skills of Experimental Group 2, in which a virtual environment was used to develop mental rotation was significantly higher compared to Experimental Group 1 and the Control Group. The result of the study suggests that using virtual environments and concrete objects together would be more effective in developing spatial skills.