Ciro Santilli @cirosantilli 37

John ([Bardeen].) and Bill ([his brother]) entered the combined seventh-eighth grade at "Uni High," Wisconsin's University High School, in the same year-John from third grade and William from fifth.

Established in September 1911, the school had been conceived as a laboratory for training high school instructors and for testing progressive ideas in education. In its philosophy and organization, Uni resembled the Dewey School. The students were accelerated as much as possible to keep lessons challenging. One goal was to "introduce pupils to high school methods and subjects before they reached the 9th grade." The fourth quarter, offered during the summer, allowed students who had missed work or had fallen behind to catch up. It also enabled the brightest students to complete senior high school in only three years

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Even with the disruption of Althea’s death, John completed all his Uni High course work by age thirteen. But as he was "a little leery about graduating so young," he and Bill decided to attend Madison Central High School for two years, taking additional mathematics, science, and literature courses not offered at Uni. By the time John had turned fifteen and Bill seventeen, the two had completed every course of interest at Madison Central. There was no longer any reason to postpone entering college. In the fall of 1923 they both entered the freshman class at the University of Wisconsin.

We have been pushed to consider it, not because of concerns about whether it is psychologically healthy for children to study here, but because of child protection laws which have come into play this year for the first time.

To summarize, internal energy and enthalpy are used to estimate the thermodynamic potential of the system. There are other such estimates, like the Gibbs free energy G. Which one you choose is determined by the conditions and how easy it is to determine pressure and volume changes.