We know that multicellular organisms  come in a variety of sizes but have in common that they are assemblies of cells . A general question that follows from this is "is there any relation between the size of an organism and the size of the cells that make it up?".
Your task today (in groups of two) begins with thinking of some possible general answers to this question, and about which ones make good (ie interesting and testable) hypotheses. You should then pick such an hypothesis and (using tools we will make available, including a microscope) collect relevant observations.