Class 2-A
At Tokyo-3 First Municipal Middle School, Class 2-A is the 8th grade class that the Evangelion pilots Shinji Ikari, Asuka Langley Soryu, and Rei Ayanami belong to. Among their classmates are Hikari Horaki (the designated class representative), Toji Suzuhara and Kensuke Aida. As part of their curriculum, the students are also provided red laptops to aid their studies (which all of them appeared to be networked).
However, in Episode 03, Toji notes that the class roster has thinned out, and Kensuke further states that the Angel attack (specifically the battle against Sachiel) forced some frightened people to move out of Tokyo-3 or transfer to other schools. In Episode 17, Ritsuko reveals that as the school is covertly designated as Code 707 by the Marduk Institute, all students in Class 2-A are potential 4th level pilot candidates, and in Episode 19, that information is relayed to Shinji.
Notes
According to the evacuation announcement during Shamshel's attack, it seems that the entire school consists of elementary and middle grade classes.
In the Japanese school system, elementary school goes from grade 1 to grade 6, middle/junior high school starts from grade 7 to grade 9, and high school begins from grade 10 to 12. Middle and high school grades are designated as "years" (i.e. Grade 7/10 = 1st Year, Grade 8/11 = 2nd Year, Grade 9/12 = 3rd Year).
For year/section designations, the first number in the class is the grade for the specific level of education (middle school in this case) and the letter denotes which of the specific section classes of that grade. This designation also applies to the classroom, since the students stay in the same room throughout the school day while the teachers for a given subject switch classrooms.
This is corroborated when in Episode 09, a student mentions that Asuka is in the 8th grade, and in Episode 17 when the old teacher tells the class that Mr. Koike is absent so the modern Japanese class will self-study.
