Which model involves the addition of a second language without interfering with the first language?

The enrichment or additive model is designed to incorporate a second language while simultaneously maintaining and enhancing proficiency in the first language. This approach values bilingualism and aims to develop a learner's potential in both languages. It creates an enriching educational environment by allowing students to draw on their first language as they acquire the second, thus benefiting from their existing linguistic knowledge and cultural background.

In contrast, other models like the subtractive or remedial model often result in the first language being diminished or lost, and the deficit model tends to focus on perceived deficiencies in language skills rather than fostering bilingualism. The transitional model usually emphasizes moving students from their first language to English, which may not support the continued development or value of the first language to the same extent as the additive model.