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
A website that has simple alphabet print outs, upper and lower case. they can be as small as a page or as big 16 pages each. All depends on your selection. And they are big enough for you to let your students draw in them (as seen here)
Also have a tub of objects on table and do not have pictures of A objects below so they find the right items Alphabet play dough mats. Easy for beginning kindergarten because the letters on mat look like real play dough "snakes".