I would say, it all depends, whether or not a large number of middle schools feed into the high school. I would say however, for schools with an large "feeding sink", the reward of creating middle school teams decreases. For instance, at our school, where students are accepted from a large area, including many strong middle school teams, less than half of our team did science Olympiad in middle school. Personally, I think it is because A) many events, especially in the physics area, are dumped down so much for middle scholars that it offers virtually no advantage against upperclassmen who have already taken many AP science classes, and B) in the case of bio and building events, event rotations occur much too frequently to really afford veteran freshmen and sophomores much advantage.
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