The abstract letters are made into concrete story characters like Ann the Ant, whose name and identity help children remember the sound of the letter. The brain works with feedback loops. Children try to sound-out and spell words in phrases and stories. If they make a mistake, the program helps them by saying the sound, and showing them which finger to use and where to find the letter on the keyboard. The brain perceives patterns and generates rules about them.
Memory is enhanced by emotions.
The brain develops fluency with practice. At first, learning is conscious and laborious, gradually becoming automatic. When the mechanics of writing or reading become unconscious, the cortex allocates more attention to the meaning of what is being written and read. Children need to connect 40 speech sounds with their letters to learn the alphabet code. The more practice they have, the more automatic those associations become.