Writing instruction ; Minoritätensprache; Minority language ; Sprachbewahrung; Ethnolinguistic vitality; Vitality, ethnolinguistic; Sprachwechsel; Language shift; Heritage language; Language maintenance ; Bilingual education ; Latin America (Spanish language in) ; Lateinamerika (span. Sprache in) ; Spanish in Latin America ; Aztekisch; Huichol; Nahuat; Nawat; Pipil; Isthmus-Nahuat; Wixárika; Tlaxcaala