I already checked in with language. How about I look into what the field of psychology has to say? Dylan William boils it down for me when he states without equivocation: Cognitive Load Theory is the one most important things that teachers need to know about. Reduce cognitive load or bust, meaning if we want children to learn we are well advised to teach knowledge in an interconnected and meaningful manner. Here are some words that would have never occurred to me to teach side-by-side during my phonics days.