Native Language Immersion Student Achievement Act - Amends the Elementary and Secondary Education Act of 1965 to authorize the Secretary of Education to award grants to schools and private or tribal nonprofit organizations to develop and maintain, or improve and expand, programs that support the use by schools, from the prekindergarten through postsecondary level, of Native American languages as their primary language of instruction.

Requires grant applicants to present the Secretary with specified assurances and demonstrations that the schools they will support have the capacity to provide education primarily through a Native American language.

Requires grantees to:

• support Native American language education and development;
• develop or refine instructional curricula for the schools they support, including distinctive teaching materials and activities;
• fund training opportunities for school staff that strengthen the overall language and academic goals of their schools; and
• engage in other activities that promote Native American language education and development.