Hi there! You may want to give a try to Scuola Club Migros, both for dancing classes and an Italian course. It's usually cheaper than other private schools (because it is partially funded by Percento Culturale Migros) but the quality of tuition is very good.
They have a rich offer of dancing classes, like zumba, Latin, tango, bellydancing, hip hop etc... As for Italian classes, they offer both private lessons or group lessons.
The school is in via Pretorio 15 (Lugano, town centre), on the 4th floor of the big Migros building. (You can't miss it.

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