YOU SAID:

my cousin bought a gun he was going to bring into school for show and tell

INTO JAPANESE

私のいとこはショーと教えのために学校に持ってくる銃を買った

BACK INTO ENGLISH

My cousin bought a gun to bring to school for show and teaching

INTO JAPANESE

学校に持って行かないの？

BACK INTO ENGLISH

But maybe you should bring them to school, no? For show-and-tell?

INTO JAPANESE

学校に持って行かないの？

BACK INTO ENGLISH

But maybe you should bring them to school, no? For show-and-tell?