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
Squishy Bag - A tactile/multisensory approach to pre-writing and writing skills. Things you need - Gallon size Ziploc bag, glitter (optional), food coloring, hair gel (dollar store) I like this better than paint.