That marble-ous child

How many marbles can be scooped up and transferred from the tray to the container using just the lid? How many marbles will go into the yoghourt pot and can they be transferred to another pot without spilling? How far will they roll if when they spill? Shall we sort them by colour or by size? And so on. 

So much to be discovered and investigated and practised. She must have been playing working with the marbles for over a hour.  Most of them date from my sons' childhood but a few from mine.