As a teacher and a mother, I feel like I am kind of in the middle when it comes to sugary treats. I think you need to acknowledge both that they are not good for you and that they taste great. So, having them for special occasions but not every day is fine.
When I was a teacher, I often had to teach the different states of matter and how states can be changed. I did my best to save this unit for Valentine’s Day. I would have students make observations about bars of chocolate. We would make guesses of how to change it from a solid to a liquid, experiment, and pour melted chocolate into little molds, and then change them back into a solid. Students could then give them to someone as a gift. (they usually sampled some in the process)
So, try it today!