4 pounds of black beans
1 Toob of space figures (satellites, space shuttle, astronauts, a space chimp, etc).
parts of 2 packs of glow-in-the-dark stars and planets
2 light-up squishy ball things (on clearance at walmart for $0.50 each)
I also added a vintage 1950's aluminum tumbler, a tea strainer ball (taken apart), a spoon, and a tea strainer spoon.
So far, Acorn is most interested in the big pink crescent moon and the tumbler - it makes a nice sound when you bang it on the counter and when pouring beans in and out of it. We just put it together last night, so we haven't had an opportunity to see what he thinks of the glowing stars in the dark.