According to scientific studies, we already know that the brain grows the fastest between 0-4 years of age, and at 5 years is almost finish growing. Based on Maria Montessori's theories, a child in this age group has an "absorbent mind". In order to prepare a child for an education system that values the curriculum above the child, I would focus on helping them develop a strong foundation before they enter it.
At the end of the 4-hour program, that is when the real fun begins! The student becomes more confident day by day as they can read more words and enjoy stories. The key is to provide a stress-free environment where they feel safe to try out their new skills. As long as they're using it every day, you'll find that at some point they'll start to amaze you with the words they can read! From there on, there's no limit to their reading potential, and you might even find them tackling more advanced phonics and words by themselves.