We had a few goals in mind: to make the orchestra a tighter ensemble overall, to focus on especially difficult spots with section coaches, and for the kids to get to know each other a little better.
The itinerary was ambitious, with an hour-and-half rehearsal the first night after dinner, then a night-hike. The next day began with breakfast and three hours of sectionals, followed by lunch, a two-hour rehearsal, and a mini-concert for parents, to show what we accomplished during the retreat.
The total working time amounted to about 7 hours of work, or the equivalent of nearly a month of ordinary Thursday rehearsals!
Intermezzo has kids from third to eighth grade, with most kids in the grade 5 to 6 range, so they were certainly pushed to their working limit, which is a valuable experience itself, but they also had lots of breaks, to help mitigate the intensity.
It looks like something we should do every year, and by the end of the retreat, the kids were expressing remorse that it was only for one night!