I have been wanting to try this activity out with my almost-four-year-old for some time now, either with salt or cornmeal. I am really glad we did! Basically, get a shallow tray and fill just enough with salt to create a thin layer. Then practice! To erase just shake the tray gently.
In the above photo she is practicing an “F”. Writing in the sand doesn’t always produce a perfect looking letter no matter how precise you try to write it. It’s a fun way to get your kid to practice though!
And my daughter would have fun just drawing in it too. She would often turn away from me and lick the salt off her fingers… as if I didn’t know what she was doing!