Teachers claim that they are presenting children with the facts and nothing but the facts. Textbooks describing historical events usually claim to give the bare, objective facts. And this is exactly what is wrong with it. The point is that it is quite irrelevant that the Battle of Waterloo took place in 1815. Today, we can still see the legacy of 'Napoleon', as people are forced to register births with the Government, use family names, use the metric system, etc.
School portrays history as a chain of events in which people are butchered to death.
Out of a whole century, history books typically pick only those events in which large numbers of people were slaughtered, died of epidemics, were led into captivity or were starved to death. This is a gross misrepresentation of what was important in the past. Wars, dictators, diseases and natural disasters may have had their impact on society, but they did not build up any prosperity, they did not contribute to progress, they only destroyed society. We could have done without this destruction. On the other hand, society would still be in the dark ages without all the people who worked hard, improved their techniques, designed new ways to raise the quality of life, etc.