Oh man, my childhood microscope, chemistry set, plastic Babbage's machine, short wave radio, all of it -- even my brother's toy steam engine -- pale in comparison to the wonder known as the Gilbert Atomic Energy Lab.
It included: a U-239 Geiger radiation counter, an electroscope to measure radioactivity of different substances, a spinthariscope to watch "live" radioactive disintegration, a Wilson Cloud Chamber to see paths of electrons & alpha particles at 10k mps, three very low-level radioactive sources (Alpha, Beta, Gamma), four samples of Uranium-bearing ores, Nuclear Spheres (used to visual build models of molecules), the book "Prospecting for Uranium", the "Gilbert Atomic Energy Manual", the comic book "Learn How Dagwood Splits the Atom" and three "Winchester" Batteries (size "C").
A Geiger counter, radioactive samples, a "Dagwood Splits the Atom" comic book and Nuclear Spheres? Yowza! Can you imagine the look on a modern Helicopter Mom's face if her kid unwrapped a present and found that inside?