3 ideas
People are born good and nearly alike in nature, and the gaps between adults come from practice and habit pulling them apart. So differences in character reflect how a person was shaped more than what they were born with, and if teaching stops, that shared nature drifts. This makes education the deciding factor in who a person becomes.
Mencius's mother moved house three times until she found neighbours whose influence would shape her son well. When he gave up his studies, she cut through the cloth she was weaving to show him that quitting halfway wastes everything done so far. The story teaches that a child's surroundings shape them, and that a parent's job is to arrange those surroundings and make sure work gets finished.
Learning follows a set order. Filial and fraternal conduct come first. Then basic facts: numbers, the seasons and the directions, and the names of things. Next come the Four Books, then the Classics, then the philosophers, and last the histories. Each stage prepares the ground for the next, so character and basic vocabulary come before interpretation.