The very experienced Puerto Escondido  Language Institute (tel. 954/582-2055, info [at] puertoschool [dot] com, www.puertoschool.com ) offers private or group lessons, homestays, tours, rock climbing, and more, across the highway from Cruz Azul cement store, above Playa Zicatela .
Alternatively, you might check out either Maress Spanish School (Avenue 2a, Norte, tel. 954/582-4159, local cell tel. 044-954/544-3658, www.puertospanish.com ) or Mendez Spanish School (Marsopas 36 and 37, west-side Rinconada district, cell tel. 044-954/108-6942).
Furthermore, at least two individual teachers offer Spanish lessons: Sheila Clarke (tel 954/582-0276, Dec.–Feb. and June–Aug. only) and Yolanda Park (tel. 954/582-0837).