i believe that allowing your child to wear jeans during his out of yeshiva time will cause him to enter the mindset that he is really not so different from the goyim that he sees on avenue J. on the other hand, girls wearing jean skirts i don’t have a problem with because lemaisa it does look like they’re setting themselves apart from the goyisha velt. this krum mindset that your son will fall into is the beginning of a VERY slippery slope. and just like dating outside of the shidduch system, Yeshiva University and falling to the deception of Matisyahu, your “bachur” will HaMakom ye’rachaim be influenced by the goyim he surrounds himself with until the Aibishter will not hold him, but ONLY YOU accountable for his inevitable intermarriage.