You don't say where you are flying from, but Seviile has many flights from Barcelona and Madrid and not so many from the rest of Europe. These can be booked via Iberia, BA, Opodo etc. I was going to suggest Easyjet from Gatwick, but had a look and saw all the added extras (typical of our LoCos) and early flight times, so I doubt you would have a happy experience. DO NOT FLY RYANAIR.
Seville is a great town. I love to while away the week there doing nothing, but grazing Tapas bars, siestas and catching some flamenco. I expect that the instruction will include local knowledge, but I loved
Casa de la Memoria for an intimate Flamenco setting - about 40 people and Flamenco by lovers of the form rather than a half-hearted tourist show.
I'm sure you'll see the Alcazar and the other standard tourist destinations. Jerez is onlly a day trip away and you can learn all you ever wanted to know about Sherry there on one or many bodega tours. If you have time Grenada (the Alhambra gives quite a different view of Islamic taste from what we normally get told) and Ronda are also well worth the effort.
I am intrigued about a combined language and flamenco course - sounds great! Would you mind posting a review?