Where do Spaniards vacation in the summertime?
 

My family (2 adult + 3 children ages 13,11 and 8) are planning to visit Spain this summer for a few weeks. I would like to go somewhere (probably coastal) where I will have the opportunity to mix with spaniards and improve my Spanish. It is also important for us that there is enough nearby to sustain us (and the kids) for an extended stay without spending all our time travelling. Any suggestions?

The north coast: Laredo, Santander, San Vicente de la barquera (in Cantabria); Llanes (in Asturias). Castellano is the principal language in that area. If you go further west, the indigenous people speak Galego; further east it's Euskera. In Santander, castellano is spoken very, very fast. Even my wife, a native Madrilena, had problems keeping up with my friends in el Sardinero.

Mid-July to mid-September is quite crowded anywhere on the coast.

Proportinaly to the number of foreighners there are more Spaniards taking their vacation in the north than in the Meditarrenean coast beaches.
In the Mediterranean coast,there are some internationaly known destinations such as Mallorca, Marbella, Nerja, Torremolinos, Playa de haro,that you will find full of foreigh tourism.
Others like Gandia, Playa de San Juan,
Cullera, Benicasim, will have more locals.
One place that I think could meet your needs is Santi Preti or surroundings in the Cadiz coast, this area is undergoing a good development offering lots of activities for young people in a very spanish atmosphere. You are going to be influence by the Andalusian accent but I will consider that as a plus.

Thank you for your input. I have been researching two areas: Costa de la luz and the Javea area (Costa Blanca). I have found much more available in Javea and at much more reasonable rates than the costa de la luz area. However, I am a bit concerned that it may be very British. I am also concerned about the heat. Our dates are June 26 to July 31. Is a/c a must in either place. Should I avoid the costa blanca completely at that time of year? Should we be considering San Sebastian or thereabouts? Would really appreciate any insights. Thanks.

In Asturias you have close at hand both the beaches and mountains. Very few locals speak english & many Spaniards vacation there in the summer to escape the heat of Castile (central Spain).
Gijon is a mid sized city which has several beaches and excellent/inexpensive rail & bus service for short trips throughout the area.

Personally, I think your question about A/C is easily answered...if you went to the beach anywhere and you knew it would probably be hot and humid, would you consider not having air conditioning???? probably not, and from my own Spanish travel experiences I would advise you to try to find A/C'd accommodations if at all possible.
If it is hot enough to be in the water then it is hot enough that you'll need to be comfortable in your hotel room...and you WILL be spending at least 1/3 of your day/night in it.

sweeneyashtray
In the spanish mediterranean coast as far as you are close to the shore, nights are not that bad. If you rent away from the coast, more than one mile, your heat or heat sensation will increase.
I will not be too concern about heat, keeping in mind that you are on vacation and you can ajust your activities and timings to your better convinience.
The norht of Spain is very comfortable heat wise, but keep in mind that there are more chances of rainy days and therefore you should have alternative plans for such dates.