You can try this at home. All you need is a small push pin, some construction paper, and a few pieces of felt for padding. Draw simple design on a piece of paper, or draw the letters to your child's name. Lay the paper on top of the felt padding. Have the child push the pin in and out along the lines, making tiny holes in the paper. Because the push pin is so tiny, it forces the child to hold it in a proper pencil grip. When it is finished, turn the paper over and you can see and feel the outline of your drawing on the back.
My two really liked this activity. I hope to encourage them to do this more often in order to help with their pencil grip. Try this at home and let me know how your littles liked it!