Summary Make bread, experiment to find out what ingredients make gas to make the bread rise, and model the chemical reaction that makes the gas. Science content Biology: Features, Adaptations of Living Things (K, 1, 3, 7) Chemistry: States of Matter, Properties of Materials (K-7) Chemistry: Atoms, Molecules (3-7) Chemistry: Chemical Changes (2, 7) Activities in this lesson Bread Yeast eats sugar and makes gas Bread: test ingredients for making gas Molecular modelling of yeast converting sugar to gas Butter Butter molecules Procedure Do the bread making activity. It has a couple of breaks, where other activities can be done. Ideas for lesson plan formats: Make dough and set it to rise. While waiting for it to rise: Show that the yeast eating the sugar makes gas for the dough to rise or Test ingredients of bread dough for which make it rise or model the chemical reaction of yeast converting sugar to gas. Shape the dough and put it in the oven. While is is cooking: Look as results of testing dough ingredients and model chemical reaction of yeast converting sugar to gas or make butter/model the molecular changes as butter is made. Eat fresh bread, with butter if you made it! Grades taught Gr K Gr 1 Gr 2 Gr 3 Gr 4 Gr 5 Gr 6 Gr 7