He may want to find out if level 2 in the high school will give him enough skill to get placement higher than the first semester course at the colleges that he is likely to attend.
Note that, for English speakers, Mandarin is considered a harder language than Spanish or French, so it may take more courses to reach a desired level of proficiency in Mandarin than in Spanish or French. For example, the intensive language courses at the DLI are 36 weeks long for Spanish or French, but 64 weeks long for Mandarin.