At first, students struggled with the meaning of the slope of the trend line and possible causes for a berry with relatively low anthocyanin content (raspberry) to be a strong radical scavenger.22,31 The room temperature acidic methanol extraction technique was optimized to extract anthocyanins rather than higher molecular weight polyphenols, but smaller water-soluble antioxidants, such as ascorbic acid, can be co-extracted with anthocyanins.32 TAs did not directly inform students of the other antioxidant contributors in the berry extracts. Instead, TAs were instructed to ask guiding questions, and students were encouraged to read the literature