Kalam says " on the whole the small society of rameshwaram was very rigid in terms of segregation of different social groups ? Please tell Answer from chapter my childhood

Dear Student, 

Your question is not clear and appears to be incomplete. I am assuming you want to know the meaning of the line. 
Accordingly, here is the answer:

It means that the society in Rameshwaram was divided into groups along religious lines. The perfect example of this was the regressive mindset showcased by the new teacher who came to Kalam's class. He did not allow Kalam to sit with his Brahmin friend Ramanadha Sastry as he was a Muslim.

If this was not what you had in mind, please re-post the complete and clear query in a new thread. Our experts would be happy to help you there.
 

Regards,