A little bit of context: we're in Germany, where, in the 5th grade, children are split into multiple types of schools, based on their academic capabilities. This is decided by the teachers based on grades, social skills and work ethics. For our son, that will be decided based on the evaluation from this year.
Now, our problem, the teacher called us in and basically told us exactly this: our son is very smart and should follow the highest academic path, however she won't be able to recommend that unless he changes the way he works. The problem is that no matter what assignment he has to do, he does is extremely fast and then refuses to check what he did. If he checks it, it's with the same rush. This is tests, homework, everything. This leads to a lot of mistakes. For example, they will be asked to copy a text on the back of the paper, so basically they have the text on one side and the have to copy it on the back, being allowed to turn the page over as many times as they like. Here, he will get about 15 mistakes for a half a page text.
This doesn't apply to maths where, even he hurries it, he somehow gets everything completely right most of the time.
School is not the only thing he hurries, it's also everything else - eating, playing, reading.
It's really important to temperate this behaviour in the next 3-6 months, at least enough to get his school work back on track. What could we do?