The purpose of this learning activity packet is to acquaint students of Spanish as a second language with letter-writing in Spanish. Upon completion of the packet, students should be able to: (1) identify some of the major differences in mailing customs between the U.S. and Hispanic countries, (2) read and write mailing and return adresses, (3) read and write informal letters at the students' level of Spanish proficiency, and (4) read and write some types of business letters at the students' level of Spanish proficiency. Verb tenses in the packet are restricted to the present and the preterite. The packet is divided into four lessons: (1) Mailing Customs, (2) Addresses and Envelopes, (3) Informal Letters, and (4) Business Letters. A self-test is found at the end of each lesson, and a series of summary exercises concludes the packet. (CLK)