Tonight's affair is slated to be a real celebration, with many illustrious alumni being present (now professors, judges, scientists, architects and artists, etc.). Several well-known bands and entertainers are scheduled. There are expected be a number of former students attending, who now live in many places all over the world.
It's unlikely that I'll ever take part in a reunion such as this of my own school. The closest I came is on a trip we took about three years ago to my birthplace (Berlin), where I made an effort re-trace the path I took to school daily as a young teenager. The building was locked (it was a Sunday); I could therefore only look at the outside gate. Many schools in Berlin were then (and are now) located within normal looking city blocks, among a mix of shops, residences, churches, etc. They may none-the-less cater to many hundreds of students through several grades. My high school is one of these.
Here's a Google picture of my high school (it's called "Leibniz-Gymnasium"). The layout is the same, but the tree in the courtyard is much bigger. Also, there appears to be a statue (shadow at the left centre in the courtyard), perhaps of Gottfried Leibniz (a contemporary of Newton) which did not exist in my days there. Leibniz is the one who came up with the mathematical techniques of integral calculus - Newton is credited to be the inventor of differential calculus. Even now, there is some controversy regarding who should be called the "father" of calculus. In truth, the two techniques are the two sides of one coin; Derek had some comments in the coincidence of revolutionary inventions on his blog a little while ago.
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One thing is obvious: time marches on, and leaves no one untouched.