Just on the OP scores. My son who did senior last year and whose (totally un-snotty) private school had 40% of the seniors get OP 1-5 (from memory) told me that he heard some of the elite schools ask their low achievers not to attend on the day the score exam (cannot remember what it is called) is sat by "every" senior. This exam is somehow used to set the benchmark for the OPs (or something like that). That way the school looks better because its score is not pulled lower by the low achievers..
Only a rumour, but could well be true if they want the money to keep flowing.
So, don't be totally fooled by the OP scores that make it to the paper.
Wylie