A+ isn't worth taking unless you can get it paid for. Since you are 14, your parents will probably pay for it so I would take advantage of that. I would not spend my own money on it though.
Employers don't value that certification very high. But, IF there are two people applying for a job who are completely equal in every way, and one of them has the A+ and the other doesn't, and neither of them have any friends or relatives already working for the company, the person with the A+ would get the job. But its really such a low valued cert that its only in a situation like I just mentioned that it will do you any good.