Writing letters in salt (this site has Montessori & Montessori-inspired activities).already have the sandpaper letter tiles.
Filth Wizardry: DIY spinny spellers and repurposing Duplo bricks. Several fun ideas for using Duplo and Lego bricks for language arts.
Preschool Letter H
Draw a letter on a pin board and have children push the pins in correct order to form the letters. (Could write numbers and even draw arrows to show letter formation sequence.) Great for fine motor skill development and letter formation and recognition
Making a Letter with Letters
a fun project for kids learning the alphabet or to create the first letter of their name for upper grade art project.