元素記号と周期表を、見て・埋めて・当てて覚える
From a picture-book mode for browsing the periodic table to fill-in-the-blank, 4-choice quizzes, and a memory-matching game, there are 10 modes for learning element symbols. It also covers electron shells, ion formulas, and chemical equations, spanning middle-school science basics through high-school chemistry. It's not directly tied to game production, but it's also a page the author built to satisfy their own urge to relearn the element symbols.