The Montessori golden beads bank game gives a bird's eye view of the decimal number system.  It is sometimes known as the 45s Layout.

The place value cards are laid out in order in Units, Tens, Hundreds and Thousands coloumns with the beads required for each number place next to each card.

This activity gives an excellent opportunity to understand the decimal system and a full explanation of the activity can by found in David Gettman's excellent book.

Ideally this is presented with a limited number of beads to match the the cards: 45 units, 45 tens, 45 hundreds and at least 6 thousand cubes (going up to the 3000 card), having the correct number of beads provides a control of error.