It depends on specifics, none of which you have provided. Just today I watched a rare film of American soldiers killing two Wehrmacht soldiers who were surrendering. The narration said it was murder and an atrocity.
Not knowing the specifics, there may have been ameliorating circumstances. In WW2 there were instances of German soldiers feigning surrender to kill Americans and General George C. Marshall gave out orders that as a consequence no prisoners were to be taken.
War is hell and IS one big atrocity. Nobody comes out innocent. At the beginning of WW2 Allied commanders stated they would never target civilian populations, but as the war dragged out with massive casualties they had little choice. It became almost routine.
There are claims of widespread atrocities and mass killings of German prisoners after the war, but a lot of this is just plain BS. "Allied War Criminals of WWII" by Paul David Cook is part truth, part lie, a good technique went you want to deceive someone is to mix up facts and lies.
There is nationalism as well as anti-Soviet, anti-American and Anti-Semitic revisionism. There are pro-Nazis who also distort history. As for mistakes or intentional deception, that is up to the discretion of the teacher. I had a teacher in the 8th grade (1981) who was a die-hard pro-Soviet communist; she actually handed out papers showing the comparative prices of groceries in the US vs the Soviet Union, "Look how much better it is in the Soviet Union." She was an utter fool.