Most will only be able to swallow two or three. Most students completely overestimate their ability to eat the pretzels in a minute. Predicting is a skill a person needs to develop to become a successful scientist. Students should notice how predictions change as more information is made available. The experience with eating a portion of a pretzel and information given about the additives should have motivated them to change their predictions.
Scientists gather as much information as they can before making predictions.
As new information is made available to them, they often change their predictions. Using a liter jar or beaker, fill it with peanuts that are still in the shell. Students are to predict the number of peanuts in the jar. The prediction process is a multi-stage process. Students should come closer to the correct number with each step.