What is Scout's assessment of Jem's changed behavior after he won't let her kill the roly-poly?help my on the question please.

The answer to this can be found in Chapter
25.

The brief answer to this is that Scout says that Jem is
becoming more like a girl. Jem has said this about Scout at times in the book, but now
she is saying it about him.

I assume that what is going on
with Jem is that he is feeling bad about what has happened to Tom Robinson.  He feels
that Tom got killed even though he never hurt anyone.  That is why Jem tells Scout to
leave the bug alone.  He tells her the bug never bothered her and so she shouldn't kill
it.