Year Six have been learning about micro-organisms (as part of our Science topic on Classifying Living Organisms). We discovered that yeast is a living thing – requiring warmth and food to survive and thrive. It was interesting to conduct an experiment involving different mixtures of yeast. We varied the water temperature and also tried adding sugar as a food source. After making predictions, we found that the resultant reaction (when both warmth and sugar were available to the yeast) produced carbon dioxide which inflated the balloon.