I love to instruct people on how to read a concert program, giving short definitions of what the words might mean: structure words like sonata, symphony, minuet, and tempo words like allegro or adagio.
Then there are the keys: Some people disassociate themselves from this altogether as if the key didn't concern them since they neither play in the orchestra or have perfect pitch. But just about everyone has sung My Country, 'tis of Thee or The Star-Spangled Banner, and has some memory of their own vocal comfort zone. The orchestra tuning to A invites every listener to internalize that reality in relation to their own voice.
One of the most interesting aspects of a program is what happens between movements of a sonata or symphony. Unlike most CDs, in which this is dead space, a truly musical performance will use the that time to build tension in the transition from one key to another and from one mood to another. In fact, most fine composers effectively compose those silences to contain extremely important information.
One of my favorite teaching memories involved some 7th-grade classes I had taught about how to read the program and how to get interested in the music in a highly participatory way. The first thing was to figure out whether the piece was serious or humorous--very important. Next was to figure out when to clap.
After a few weeks of class I invited them and their teachers to a recital in which I deliberately programmed a variety of serious and tongue-in-cheek works. When I finished the Mozart sonata that trailed off into nothing the kids burst out laughing, much to the embarrassment of their teachers, who were extremely surprised when I then congratulated the students on their response which proved that both I and Mozart had succeeded in getting a point across. The teachers apologized to me on their way out.
