Heat Reinvented: Using a Lunch Box-Design Project to Apply Multidisciplinary Knowledge and Develop Invention-Related Practices.

If the student does not feel the hot and cold difference between the two sides after two seconds, the teacher should ask the student to first disconnect the Peltier tile from the batteries and then check if there is any incorrect connection in the circuitry. To prevent students from taking the criticism personally, the teacher can ask students to present their classmates' work. The teacher needs to be cautious as it may get too hot for students to hold and should explicitly instruct students not to continuously hold the tile for more than five seconds while it is connected to the batteries. The teacher can ask students to think about how to improve the cell phone or iPad stands they have seen before and help students realize that small improvements can be inventions, too. [Extracted from the article]