A slightly rainy Friday in San Francisco saw Analy, Jesuit, St. Francis and Palo Alto High Schools, plus LAB XVI brave the elements to spend the day with us, working and singing together.   It's a long but rewarding day during which we work with the individual choirs on their individual numbers, and Fred leads rehearsal of everybody in the  tutti numbers which were Mozart's Ave Verum Corpus, Palestrina's Kyrie and Gloria, and I'll Soar Away.