According to co-constructivism theory, learning is a social activity. Students are expected to find many opportunities at Science lessons to construct their collective culture and co-construct their culture since science lessons tend to collaborate. This study aims to develop a scale that measures the co-constructivist environment at 7th and 8th Grades science courses. For this reason, the scale developed by the researchers has been applied to 238 7th and 8th grade students. Exploratory Factor Analysis has been applied for 47 items. As a result of factor analysis, 20 items have been omitted, and the remaining 27 items have been grouped into five factors. These factors explain 64.371% of the total variance. Cronbach Alpha value of the scale is .950. The values of item-total and item-remaining correlation are significant (p<0.01). Moreover, the item discrimination value obtained from the difference between mean points of bottom and top 27% of the groups is significant. As a result of confirmatory factor analysis, goodness of fit indexes are seen to be acceptable (RMSEA=0.084; AGFI=0.70; SRMR=0.064; CFI=0.91; NNFI=0.09, [chi-squared]/sd=1.93). It was found that the qualitative results mostly coincided with the results of the quantitative study.