Sandwich bags, and let the kids sort for their purpose. Allow me to explain.
I don't recall ever having these Lego sets with build instructions (70s), just some standard shapes and colors.
I remember in the 90s being frustrated that I couldn't find generic containers and had to purchase these pre-packaged designs for my kids (expensive). I soon discovered that my kids lost interest after the first build leaving me frustrated and wishing I had just gotten them a cheap jigsaw puzzle. After consideration I intentionally mixed all the pieces from multiple sets and challenged them to make something on their own.
The sandwich bag idea was my son's and he segregated the pieces on his own.
I don't recall ever having these Lego sets with build instructions (70s), just some standard shapes and colors.
I remember in the 90s being frustrated that I couldn't find generic containers and had to purchase these pre-packaged designs for my kids (expensive). I soon discovered that my kids lost interest after the first build leaving me frustrated and wishing I had just gotten them a cheap jigsaw puzzle. After consideration I intentionally mixed all the pieces from multiple sets and challenged them to make something on their own.
The sandwich bag idea was my son's and he segregated the pieces on his own.