A project called 'Science Education and Diversity' (SED) funded by the European Union's FP7 programme was initiated by the University of Exeter in 2010 and was simultaneously conducted by the six partner countries, namely UK, Netherlands, Turkey, Lebanon, India and Malaysia. The Indian chapter was conducted by the Homi Bhabha Centre for Science Education and was completed in 2012. It aimed to understand the relationship between science education and diversities. The present paper gives a broad summary of phase three of the project which was an intervention carried out in 3 secondary schools of Mumbai, where the topic “Biological diversity” was taught to class VIIIth students. Using a design based pedagogical framework an attempt was made to use the topic to also address the diversities in human beings (gender, religion, culture, etc). The preintervention findings showed that teachers largely ignored addressing diversity in the classroom in their teaching-learning activities. Post-intervention too there was not much change observed in the teachers‟ stance. The paper provides implications for addressing diversities through the school curriculum.