It's a very difficult question to address in terms of "impact". We're talking about emotional, mental and social impacts, which are, by definition, hard to measure. I think the propaganda of the public school system in Germany, which had been purged of liberals, Jews and dissenters, would have the most lasting effect. What if, as a high school senior, you discovered that everything you had been taught (the Reich lasted for 12 years) had been a lie? Some of Hitler's most devoted followers were young people who had no memory of anything other than National Socialism and the Fuhrer.
I agree with the above posts--the propaganda itself instilled a sense of superiority for the Germans (in particular, the Nazis) and an inferiority regarding the Jewish population. The cartoonish depictions of the Jews with the over-large noses and their beady, untrustworthy eyes, helped. Children are the best targets as they are so much more impressionable than adults.
It might be interesting for you to study examples from textbooks in Germany at the time that taught German youth about their ancestry, their rights and in particular the status of Jews among them, who were caricatured, ridiculed and demonised and despised. They were variously depicted as bogeymen and a danger to the purity of the German Aryan bloodline.
I think that the Nazi use of propaganda was one of the reasons why the Holocaust ended up happening. In my mind, being able to successfully peddle the spirit of belonging to the Nazi party was something that proved to be quite effective. Hitler understood very well that in order for the Nazi propaganda to be worthwhile and meaningful, it must be aimed at the general population: Propaganda must always address itself to the broad masses of the people. The implications of this idea are profound. The first is that the Nazis understood that propaganda was to be aimed at the larger general politic, and not a select group. This tied into youth quite well in that it was intended to create a system whereby youth understood that success was synonymous with acceptance into the ranks of the Nazis. In making its propaganda part of the accepted social norm, the Nazis were able to ensure that they appealed to one of the basic elements of adolescence. The adolescent need to belong helped to feed the effectiveness of Nazi propaganda upon the mindset of young people. Consider how the Nazis were able to target much of what they preached to young people:
A pamphlet "You and Your People", given to children at fourteen, when they left school, urged on them their unity with the Volk, their ancestry, and the vital importance of their marrying within their own race and having many children.
This was critically important in how the Nazis were able to target their propaganda into the lives of young people. In merging the Nazi goal with accepted social norms and ensuring that young people were a part of this vision, appealing to their desire to belong, the Nazis were able to be very effective with their propaganda with young people.