My 5 year old son does dance. This is his third year (would have been his 4th, but he decided not to do t last year). He does a combo class (tap/ballet) one hour per week. The class costs $360 per year plus $70 for the costume, and $15 registration fee. I do get a bit of a discount off the tutition because I have 3 students at the studio (DH, DD and DS).
DD 11 also dance (her 9th year). She does 50 minute classes once per week each of tap, jazz, ballet, hip hop, street tap and modern, and she does a private class (duo), 30 minutes per week, this year he partner is her Dad

Generally tuition for each class is $90 every quarter, but the more classes you take, the more discount you get, so that 6th class only ends up costing like $40 per quarter. Her private class is $20 per week (plus the $20 per week for DH). I think her classes end up close to $500 per quarter. Her costumes this year added up to about $500.
Additionally, there are photo sitting fees (that is optional). I think including the recital tickets, photos, costumes, tution etc. that the dance studio cost about $3000 this year for DH, DD and DS.
DD has also been in Girl Scouts. It is only $10 to register for the year, but there are extras that get added onto that...most of the activities have some small additional charge, ($5 here, $18 for that, cookie sales on top of that, etc). Really nominal $$ amounts, and girl scouts offers financial aid if you need it.
DD main outside activity beyond dance is Girl Scout Day camp in the summer. That costs about $150 for a week, 8-4 and the bus transportation is included.