In a recent session here at Saint David's with DNALC educator Mrs. McKechnie, the boys completed their "Better Milk for Cats" lab. The boys had learned that most mammals, including cats, lose the ability to process the lactose in milk as they get older. (Some humans have a mutation in their DNA that allows them to continue to process milk into adulthood.)
First, the boys made lactase enzyme beads. In a follow up lab, they changed a variable, such as the amount, color or shape of the enzyme, to see if it better broke down the milk.
Through labs like these, our boys experience for themselves the various important steps of the scientific method, such as "fair test" in an experiment--the changing of a single variable while other conditions remain constant.