The story of someone spending a year building, selling and giving up on [Knack](http://knackforteachers.com/), an online grade book for teachers. Some interesting lessons learnt, including this part about why his app failed:
> Teachers say they love tech. Some blog about it. They tweet about it in #edchat and #edtech. They even coin their own special tech terms. This is a farce. Talking about tech and being on _the Twitter_ make teachers look good to administrators and to the public. They can add “Technology Committee Member” to their resumes and congratulate themselves for being innovative. But using tech to do work requires a small minimum of effort and change, and any amount of these is too much for teachers.
Overly harsh, but true*. There’s a good debate about this on the [Hacker News thread](http://news.ycombinator.com/item?id=3024147), where the writer clarifies what he meant in a comment: that he’d made a mistake assuming teachers would pay for a tool that they had to spend time acclimatising to.
* I say this as a former “Technology Committee Member” and a current app developer.
By the way, tech posts are generally cross-posted to the [company blog](http://tinkertanker.tumblr.com), along with pictures and videos of us [doing stupid things](http://tinkertanker.tumblr.com/post/10272286361/tinkertanker-exercise-day).