Three near-monodisperse poly(2-vinylpyridine) (P2VP) latexes of 380 nm, 640 nm and 820 nm diameter were prepared by emulsion copolymerization of 2-vinylpyridine with divinylbenzene using a poly(ethylene glycol) monomethacrylate (PEGMA) macromonomer. Each latex proved to be an effective particulate stabilizer for the production of long-lived foams by either hand-shaking or using foam columns. SEM studies confirmed that each dried foam contained well-defined latex bilayers, suggesting that the original air bubbles were stabilized with latex monolayers. Dried foams prepared using the 380 nm latex exhibited interesting optical effects when viewed in reflectance mode. This is most likely due to light diffraction by the latex bilayers, since the mean latex diameter is approximately half the wavelength of visible light. These PEGMA-P2VP particles undergo a latex-to-microgel transition at low pH. Such swelling causes catastrophic instability within wet foams due to microgel desorption from the air-water interface. Thus these latex foams exhibit pH-responsive behavior.