Had when i worked in a preschool and kids love them! I would use colored sand instead of white salt. DIY salt tray with alphabet cards. Easy to make and kids have fun smoothing out the salt after correctly making the letter
Fine motor activity (for indirect control of a pencil and a paint brush): Tweezing sunflower seeds, then roast or bake with a little oil, hing, black salt, as a snack offering for Krsna. ( you would probably need to grow that sunflower first!