How do they take part in the education system until they can speak English?
They should be in a class to lean English when they first enter the system and until they can learn enough to function that should be their only class.
We don't have an "official language".
Most of these kids in ESL programs also place them in remedial classes.
They follow along in PE/Gym class.
They can do math problems.
The vast majority of the kids are Spanish speaking, and in my area, we had/have bilingual teachers who speak Spanish and English....who are specifically teaching these kids for other classes besides ESL.
In elementary school, the kids are lumped together into one class.
In Middle/Junior/Intermediate/High School the kids take multiple classes; some as ESL, others where they are in science classes (as an example) with other kids in their same position, and in some cases (like Gym/PE/Spanish) they are in class with the general population.
Learning Disabled kids are often treated the same. As are the mentally handicapped who are high enough functioning to attend school with the "regular" kids.
They aren't taking AP History or Creative Writing classes.
But in my area, it's a total melting pot. So the district actively works to make this happen to accommodate. I can see how this might be problematic in districts that have less diversity.