This was a short book (maybe less than 20 pages) that I probably read around 1988 or so in elementary school. The protagonist is a young boy, I think in Mexico. His family does pottery, and he's particularly fond of making clay horses, something his family sees as wasteful because what they sell are pots (I don't remember exactly how they make the pots, although my brain is trying to suggest it's the "spiral ropes of clay" kind instead of turning it on a wheel), and his taking time to make the horses is seen as frivolous. Near the end of the book, he's come home, where the tourists are waiting for a class or demonstration, but his mother or sister is not there, so he steps up, and shows them how to make a clay horse, starting out shaky, but getting more confident as he continues. Near the end, he realizes that his family is watching him. After the class/demonstration, they tell him that they now see the value of him making the clay horses, and he feels more accepted by his family.
Big horse, little horse by Martha Goldberg
The Bulletin of Children's Books review is:
Mateo wanted to buy the beautiful horse that a neighbor was going to sell, but his family was too poor. The boy consoled himself by making a clay horse, and he found that his work won the approval of his mother-an expert potter-and the requests of tourists that he make more for sale. Mateo decided that he would become one of the fine potters of the village. A slight story that has little direction; Mateo shows an appreciation of creativity, a sense of responsibility, and an acceptance of loss ... but very little happens. The boy has made pottery before, he simply gains confidence. Another weakness of the book is in the phrases used by the characters; the family is speaking Spanish to each other, so there is no reason to use the sort of dialogue which a Mexican might use in speaking English: "Let it not repeat itself .. ." or "Also have ready the clay."