Depends on age. Modern plastic tatt made in China for little children, I have zero time for.
Old play money made out of brass from the Victorian era or even older play money from the 1980s and earlier in good condition has some interest. I bought this group of brass and zinc coins from the 1880s a few months ago.

All of these are 12mm in size and designed for children. Not super rare, but very interesting stuff.
Collecting old play money would make an interesting hobby, as the sets were often made on cheap and easily destroyed materials like paper, cardboard and low quality light plastic, that did not last very long due to rough play and poor construction. At least before 1920, play money was likely to be made out of cheap metals as plastic did not exist. Paper and cardboard playmoney exists from this era but is quite rare given its fragility. However by the 1940s cheap plastic made its entry and by the 1970s I remember numerous “Bank of Toyland” play money sets that had tissue paper notes and very cheap plastic coins I kept losing or breaking.
I love coins. Especially silver, gold and anything really old.
Member of the Royal Numismatic Society of New Zealand and the Auckland Numismatic Society