Model 90:10
In the 90:10 dual language immersion (DLI) model, the target language (in this case, Spanish) is used in kindergarten for 90% of the instructional time and English is used for 10%.
At each grade level, the amount of instruction in English rises by 10%, and is considered a "sequential literacy" model , as literacy in the target language (Spanish) is developed before moving on to formally developing literacy in English.
While learning the same curriculum as mainstream classes, students are taught primarily in Spanish during grades K-3 with a gradual increase in English instructional time until a 50:50 balance is obtained at 4/5th grade.
See the chart below for dual language instruction by grade level.
"Partner Language" or "Target language" is the minority language which in this case is Spanish.