Context-Based Learning (CBL) and learning through developing and using models are two important teaching approaches for chemistry conceptual understanding. We aimed to examine the influence of a CBL approach on students' understanding of Multiple Models of Knowledge Representations ("MMKRs") and "multiple molecular representations." Research participants included high-school students in three different research groups. The "context-based group" (N = 271) studied food chemistry in a CBL approach. The "traditional group" studied according to the traditional curriculum (high-school organic chemistry), and the "traditional + food group" studied according to the traditional curriculum, with the addition of food-related topics (N = 99). The "context-based group" had a greater effect on increasing students' ability to understand and relate to "MMKRs" and manipulate and connect among various "multiple molecular representations" (both indicators for conceptual understanding in chemistry). Food chemistry topics were also beneficial for students who did not learn in a CBL approach, however, with a lower effect. More students in the "context-based group" have shifted to being high achievers. Additionally, low-achievers have progressed significantly more than medium and high achievers. This research connects CBL to aspects of the practice of 'developing and using models' in chemistry, and a way to look at, and assess, conceptual understanding in chemistry.