As an educator, a large part of material design is finding what works for a given class of students, and finding ways to scaffold a given class content (i.e. simplifying through achievable steps). One such instance for me was teaching the passive voice to beginner, EFL high school students in Japan, e.g. 'Lisa was seen by Jack'. Successfully forming the passive voice involves a complete understanding of all the syntactic and morphological changes a sentence undergoes.

Going from an active sentence ('Jack saw Lisa') to a passive sentence ('Lisa was seen by Jack'), there is movement of the object to subject position (with a change in form for pronouns), the tense of the verb in the active sentence is used to determine the tense of 'be' in the passive sentence, the past participle of the main verb is added, and the subject is moved to the object of the preposition 'by' (see explanatory GIF).

(Near-)Native and advanced level English speakers do all that in their sleep, but for beginner EFL learners, it can be challenging learning it for the first time. It's just a lot to take in. After a couple of trials and errors, I was finally able to create a successful lesson, complete with a scaffolded worksheet and an accompanying PowerPoint/ Keynote presentation (sped up below as the GIF). Through this combination, I was able to walk my students through the activity step-by-step. By the end, they were working in reverse: creating active sentences from passive ones!