Cool Science Tricks (2005)
daveroot.neocities.org
daveroot.neocities.org
No doubt if you examine each one of these kinds of tricks there are some that are better than others, but I think collectively these kinds of things sparked curiosity and caused children to start to look at the world differently, question things. It might also be argued that this is the start of the path towards either a pursuit of the sciences or at least science literacy.
I hope that there is something replacing these (or science books for the younger set in general) because I would hate to think generations of kids are missing out on this kind of mental stimulation.
Edit: Kenneth Swezey, as an example, had a number of "science trick" books many years ago; some of them a little more sophisticated and targeting more of a teen audience:
https://archive.org/details/chemistrymagic00swez
The Book of Experiments (1958) [pdf] - https://news.ycombinator.com/item?id=32115354 - July 2022 (42 comments)
might be a fun clickhole to figure out what this was called in its time. Like, what was on the posters?
the first section of whose book Technica Curiosa, titled Mirabilia Magdeburgica, was dedicated to von Guericke's work. The earliest reference to the celebrated Magdeburg hemispheres experiment is on page 39 of the Technica Curiosa,
That title is certainly closer to "Tech Demos".