I'm 20 years old, but I'm really interested in ballroom dance. Are their classes in PA that I can take? and is?

It's never to late to learn something new. I was 30 when me and my wife learned ballroom dancing and several other dances. Now we are 49 and we dance all the time. We never competed so I can't tell you what the requirements are. When you see and instructor ask them about the requirements.
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No it's not too late. My friend also started Ballroom dance when he was 20 and now he competes (and he's great). Yeah it would be better to start while you are young, but if you are talented and practice a lot you can become a really good dancer. First take some classes for beginners(go to Ballroom Dance Clubs/Studios) and when you feel ready to challenge yourself in more intermediate level , just go for it(the more challenge, the better dancer you are). Probably the most important and sometimes very hard thing to do is to find a good dance partner. Once you find one (and if you are serious about competing) practice as much as possible (I would recommend every day, about 2 hours). Taking some private lessons is recommended; however they are pretty expensive ($45-$120 and up for 45-60 min). So my suggestion is to take some group classes first to practice and get some basic steps.And later, when you feels ready to polish your technique take some private lessons. Anyway, you can do it!
I hope it helps
P.S. Just dance :):):)
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