All the letters of the alphabet in their very own pure linen sack. On top of that, we added the numbers 0-9, too. The young one can stack them, count them, learn the letters and spell the first word.
These wooden blocks are properly old-school. They are made of solid wood and not treated with anything. Their color can vary a bit along with the natural color variation of solid wood. The sack is a different matter. You can throw it in the wash and be merciless with it.