Most colleges say that if a student takes AP, it has a positive impact on their college application. AP courses are designed by college faculty and AP teachers to make sure that AP students everywhere are doing college-level work. Admission offices know this and like to see students challenging themselves.
If your child feels academically prepared for college-level work, they should consider taking AP. Getting a B in any course is a good grade, and many high schools give the same numerical value to a B in an AP course as they do to an A in a standard course when they calculate grade point averages.
Another thing to consider: Getting a B in an AP class could prepare your child to get a score of 3 or higher on an AP Exam, which could earn them college credit. That means one less class they need to take and one less class you have to pay for. See which colleges grant credit for AP scores.