I use this printable to track my students' knowledge of sandpaper letters. I make it into a little cue card booklet and put it at the shelf.
The four groups of letters are organized into four rows, respectively. After I introduce the letter, I draw one line beside the letter (e.g. |a ). Then, when the child becomes more confident, I gradually add three more lines around the letter to make a square. A square means the child has mastered sound of the letter consistently.
This is a great way for me and other teachers to keep track of where each student is at each week.