It is unsurprising that you are fearful of teachers abusing the power of ClassDojo by doling out unwarranted negative feedback to their students. This article is an example of the behavior you so fear. I am a huge supporter of negative feedback, when used responsibly.
Responsible feedback states a goal and a consequence, assesses performance, and issues the consequence. Here’s an example: Natasha Singer, I expect all articles I read to make claims that are supported with sufficient evidence, otherwise they aren’t worth reading (Goal and Consequence). I don’t believe that all of the points made in this article are backed up with sufficient evidence (Assessment). Therefore, I will no longer read articles by you, and am less likely to read Times’ technology articles because this was a poorly researched piece (Issue consequence).
For a second example, I will use one of yours, “ ‘I’m going to have to take a point for no math homework’, Mr. Fletcher said...” This is constructive negative feedback as long as Mr. Fletcher has stated his expectations and consequences in a structured policy for his students. There is a clearly stated goal, the student did not achieve it, and there is a consequence for not achieving it.
You have properly identified some solid goals for ClassDojo, (1) Keep student data secure (2) Don’t sell student data (3) Don’t reward negative behaviors (stigmatize children). However, you did not provide solid evidence to support the claim that ClassDojo does not achieve these goals. Sam, Liam and the ClassDojo team did a much better job defending their efforts to achieve these goals. Yet, you still acted in a position of authority and issued a consequence in the form of a negatively slanted article of their product.
Every mistake is an opportunity for growth. The fact that the ClassDojo team could so quickly refute your points means that in the future it would serve you to ask more targeted questions in order to shore up your argument (this is advice, not feedback). If there is further evidence to support some of your claims I would love to hear it, because I also fear that teachers may end up dishing out unwarranted punishments.
Thank you for the article and highlighting very important goals that all education companies, teachers, and parents should be concerned with.
For a much better article on feedback than mine, read Grant Wiggins' piece on the topic: http://www.ascd.org/publications/educational-leadership/sept12/vol70/num01/Seven-Keys-to-Effective-Feedback.aspx
Full disclosure: I trust teachers. I taught for 8 years and work in instructional design. ClassDojo’s success does not directly impact me. However, they are a company that trusts teachers. I support organizations that trust teachers. When organizations that trust teachers get a negative image, it usually supports the predominant culture that permeates our less informed public.