Is It Possible Wear Invisalign on Upper Teeth Only?

But may be more difficult with only the upper arch treated. Sometimes to make room for one arch, the other arch needs attention as well. I would say it is never too late for braces, as the oldest patient we have treated with braces was 74. 15 is a LONG way from that...!
There is no extra cost for one arch vs two, so while you COULD do upper arch only, I would recommend both.

It is possible but is not recommended because
only treating one arch can result in bite issues. We not only align the teeth
but also give all of our patients a stable bite by treating both the upper and
lower arch.

At 15 many of your friends are probably in braces. You would have them off by senior prom for sure. The problem with invisalign is that many dentists and orthodontists struggle with the fine tuning and moving the teeth to the final spot where they look the best. Also, you may be seeing that your front teeth appear to be the only ones needing work while an orthodontist may see other things that can be improved like the bite. I would go get a consultation and see what they say.