Step Mom wants to volunteer at sons school

I have an only child. His step-mom has recently asked me if she could volunteer in my place for a school field trip. I nicely said I plan to attend, but I don’t take issue if you would like to attend also. His dad will not be there. Is this normal and should I be o.k. with this?

I believe that she is trying to make a relationship with your son, and I think that her desire to have a nice relationship with him would be normal. How you feel about it is up to you, but I would take your child’s interests in mind with how you express your emotions on the issue.