IQ differences between groups are prevalent within the classroom. Groups with lower IQs, Blacks in particular, have shown lower cognitive performance than their peers and are more likely to experience difficulty in the learning environment. According to the Spearman hypothesis, racial differences in the general intelligence factor (g) are strongly correlated with racial differences in IQ (Pesta and Roznanki, 2008). Teachers who know this information can harm their students. They may assume that because a student is black, they are less able to grasp information and have lower expectations of that student. Having lower expectations could lead students to not do their best and give in to the self-fulfilling prophecy that they are less intelligent and unlikely to succeed in the future. Research also indicates that black students may be slower to process information in class, which can cause them to fall behind. Educators need to be aware of these differences and practice alternative teaching styles. They should allow enough time to cover the material so that all students are able to grasp the information.