It might be helpful if you (or he) would specify what population. The German one? Or maybe the European population or global population as a whole?

Expanded from an earlier answer of mine

The OP's memory of their schoolbooks is more or less correct. Jews may have made up ca. 1% of Weimar Germany's population, but they were more likely to be professionals and middle class status. This was not the result of some sinister Jewish conspiracy, but the natural result of long-term trends.

One of the overarching facets of Central European Jewish life over the course of the long nineteenth century was the growing professionalization of Jews. Long-standing cultural commitments to education as well as Jewish participation in the Enlightenment contributed to conditions that allowed Jews to rise up into a bourgeois order during the drawn-out process of Emancipation in the various German states. Legal and social restrictions against Jews certainly remained an ever-present reality for German Jews and the professionalization of German Jews favored occupations that were much more open to Jewish participation. Fields like medicine, the law, and journalism did have a strong Jewish presence in nineteenth-century Germany, although Jews did not dominate them as many antisemites held. Ironically, state antisemitism likely contributed to this long-term trend of professionalization by cracking down on occupations traditionally associated with Jews such as hawking wares or pawnshops. The professional fields Jews tended to enter into were also comparatively low-status in mid nineteenth-century Germany. It was only by the latter half of the nineteenth century and early twentieth century that fields like medicine started to gain in prestige. And some professions like the law or journalism never fully got rid of their associations with obscurantism or unsavory associations with mass modernity. Additionally, it also bears stressing that while a large portion of German Jews were becoming middle-class, there was also a number of poorer German Jews whose numbers were not insignificant. There were Jews among the working classes and also refugees from tsarist pogroms. Nonetheless, the collective picture of German Jews by 1900 was one that had arisen to a respectable bourgeois status.

As the social position of Jews changed, so too did the antisemitism in Western and Central Europe. Biological antisemitism, pioneered in the nineteenth century by the likes of the French racial theorist Arthur de Gobineau, began to displace religious-based antisemitism such as the blood-libel. Antisemitism also adapted to new fears about both industrialization and immigration. Fears of Jewish bankers and industrialists controlling the global economy became more common in the fin de siècle and popularized by the likes of Lueger's Christian Socials or tracts like the fictitious Protocols of the Elders of Zion. Adding to this brew was a refugee crisis of so-called Ostjuden (Eastern Jews) from the Russian empire. Pogroms targeting Jewish communities in the Pale of Settlement began with the assassination of the Tsar Liberator Alexander II and continued intermittently through the First World War and Russian Civil War. This led to a good deal of Russian and Ukrainian Jews to make their way into Central Europe. Unlike the largely acculturated Central European Jews, the Ostjuden were largely unassimilated and significantly poorer than their Central European counterpart. As such, these refugees hewed to preexisting stereotypes and antisemitic tropes about alien and dirty Jews who refused to move with the times. This antisemitism in a new key often blended older expressions and modes of antisemitism. Anxieties about Jewish moneylenders soon gave way to concerns about global finance. Likewise, the blood libel became stripped of its religious connotations and instead became reflective of Jews' innate depravity.

The First World War helped foreground this modern form of antisemitism. Not only were there more Jewish refugees from the East, but Jews became a question mark with the increased importance of nationalism in fighting the war. European nationalism had a strained relationship with Judaism in which their confessional identity made them outsiders to the larger nation, and the war sharpened this distinction, especially for states that found themselves under acute wartime stress. In Germany, fears of German Jews shirking their patriotic duty led to a census of the frontlines in 1916 (which ironically proved that Jews were more likely to serve on the front). But despite the evidence of the census, the sentiment that Jews did not pull their own weight was not uncommon in both Germany and Austria-Hungary during the war and after. Antisemitic variations of the Dolchstoßlegende were also not uncommon, especially among the postwar Freikorps and the radical right. The Bolshevik revolution in 1917 also gave new ammunition for antisemitism and antisemitic discourse highlighted the often fictive Jewish background of the Bolsheviks as evidence that the Jews were controlling both capital and its ideological opponent, communism, in a concentrated plot to destroy the West.

This antisemitic invective often picked up on existing facts, such as prominent Jews in banking or the government like Walther Rathenau, but twisted them all out of proportion to reality. Moreover focusing on raw numbers also sidestepped inconvenient developments that contradicted a picture of Jewish domination of German institutions. Jews did have an outsized importance in German banking in the early twentieth century, but these were private, family-owned banks. Established firms like the Bleichröder bank, which was Bismarck's personal banker, were giving way to larger conglomerates like Deutche Bank. Many of these new firms were founded by gentiles and also had the character of the emerging modern complex corporate structure. There were Jewish directors for institutions like Deutsche Bank, but the very nature of these impersonal institutions made them easy to replace and keep the status quo. This made these concerns quite conducive to later Aryanization after 1933; the directors could purge their Jewish colleagues but more or less keep the same corporate structure. This was not the same experience as a Jewish family-owned businesses, which were already vulnerable due to declining revenues, which either had to sell outright or relocate outside of Germany. Both options during the Third Reich were costly and prone to exploitation as the Nazi state made fleecing of Jews legal.

Jews during the Weimar period were themselves fairly well-integrated into German society, but that did not eliminate antisemitic barriers. Men like Rathenau were the exception for Jewish success as there still were significant social barriers to advancement within German institutions. Nonetheless, this national minority had become quite professionalized and middle-class as a whole. The resurgent antisemitism of the war and early postwar years did alienate some German Jews from society and there was a growth to the political fringes of Zionism and communism. But Weimar's Jews for the most part tended to support the Republic and the various center-left and center-right liberal parties. But they were far from a powerful faction within Weimar politics as Jews at best comprised of around 1% of the German population.

Weimar's Jews might have been loyal to the Republic and its political parties, but this was largely a one-sided loyalty. Jews only managed to serve as deputies in the SPD or liberal parties in the Reichstag. For all of the antisemitic conspiracies about a Jewish-dominated KPD the Weimar KPD's leadership consciously decided not to put Jews in prominent positions within the Party. Edmund Silberner's research into this question estimated that in 1927, Jews accounted for 0.7 % of the KPD's members, although exact numbers are difficult to gauge since the KPD did draw in individuals with Jewish ancestry who were non-practicing or did not regard themselves as Jews. The right-wing and conservative parties like the DNVP largely had no Jewish members and their platforms often used antisemitism for electoral ends. This does not mean there were not conservative or right-wing nationalist Jews in Weimar. The Austrian-Jewish journalist Joseph Roth recalled an incident in which a Jewish banker welcomed Hitler's ascent to power and claimed that Hitler would only use violence against poorer Jews that deserved it, upon which Roth slapped him in the face and called the banker "Jewish swine."

Courts as in courthouse or court as in monarchy?