The Malaca Instituto,
www.malacainstituto.com, in Málaga is highly accredited and after 3 visits I can attest to their excellence. I have friends who have tried other schools and have been disappointed. There a several good schools in Spain but you do need to be careful.
MALACA INSTITUTO
Quality control: Our teaching, teaching materials and facilities are subject to rigorous and independent inspection by the following organisations: Instituto Cervantes, EAQUALS, University of Alcalá (CEELE), EFQM and IALC.
“Recognition” and Credit : courses offered by Malaca Instituto are “recognised” for Bildungsurlaub by various German state governments, by the CSN in Sweden and for Academic credit in the USA.
Teaching philosophy: Malaca Instituto has developed its own teaching “philosophy” combining many aspects of the communicative method with a structured approach to the learning of grammar.