Kinetic Theory and Bernoulli's Principle are fundamental concepts life science students can use to explain a variety of important biological phenomena. Based on paired student interviews we established that many UNE students had no molecular models to describe fluid behavior, and what models students did have were typically flawed. We developed simple experimental activities and questions to help pinpoint student preconceptions regarding ideal gas behavior and a fluid dynamics concept relating to Bernoulli's Principle. Students were asked to use multiple representations (diagrams, graphs, math and verbal descriptions) to explain these experiments. Our research suggested that understanding Bernoulli's Principle was helped by having a conceptual understanding of kinetic theory, in particular equating pressure with particle collisions. Based on these results a multi-representational "modeling centered" ideal gas law lab, using semi-quantitative diagrammatic tools, was created. We tested the lab on our spring 2013 general physics students in order to investigate the impact of the improved models on Bernoulli's Principle comprehension. The same students were post-tested on a new set of similar ideal gas and fluids dynamics problems with the results indicating substantial improved gains in answering fluids statics questions and modest gains on Bernoulli Principle questions.