Comparisons with traditional classroom environments showed that the jigsaw classroom has positive effects on academic performance , self-esteem and attitudes towards other ethnic groups . The technique has since been applied in hundreds of schools across North America . From its initial application at third - to fifth-grade school level , it has been expanded to other educational levels . This success encouraged Aronson to apply his research to other policy issues including energy conservation and the treatment of the elderly . In the aftermath of the Columbine High School massacre , Aronson advocated for jigsaw classrooms as part of an approach to defusing the social divisions underlying school violence
Columbine High School massacre
Columbine High School massacre
Elliot Aronson