and holistic approach to the teaching and learning of mathematics. Mathematics and its other STEM-related disciplines are generally challenging to many students and therefore it pays to enlighten the subject in ways that are appreciated by the learners. The use of humour by a teacher in classroom settings is one technique that points in this direction. Hence, although the use of humour in the class (often referred to in the literature as classroom humour or instructional humour) is just one technique out of many, it may be the key to the elusive concept of "best teaching practices" or "instructional best practices" in classroom settings.Chapter 4, "Impact of Integrated Science and Mathematics Instruction on Middle School Science and Mathematics Achievement", documents the impact of the Middle School Math and Science (MS)2 Integration project, employing the results of the internal evaluation of this intensive teacher training model for integrated science and mathematics in middle school. The authors mention that although students in (MS)2 classrooms are more likely to have higher achievement scores, the frequency of integrated instruction opportunities also significantly predicts student achievement, particularly in mathematics classrooms.Chapter 5, "Grade 10 Girls' Experiences in Choosing STEM Subjects in Rakwadu Circuit, South Africa", acknowledges that few women pursue STEM careers, although all learners in South Africa from Grades 5 to 9 study mathematics and general science, which combines physics, chemistry, biology, and earth science. However, fewer girls choose to study science subjects in Grade 10. Schools have a good balance of boys and girls studying general science subjects because they are compulsory until Grade 9. In Grade 10, learners choose to study arts, business, or STEM subjects. It is at this level that the number of girls in STEM subjects drops dramatically, leaving the boys to continue unabated, sustaining the hegemony of the masculine gender in STEM subjects. Hence, the study seeks to understand girls' experiences in choosing STEM, to assist education stakeholders in motivating and advocating for more girls to choose science subjects and STEM careers. The case study in this chapter focuses on ten girls who decided to study science out of 145 girls who attended general science in Grade 9. The study reveals that personal factors, anticipated value, the class environment, home influence, and social influence contributed significantly to the girls' choices. If such a drop from Grades 9 to 10 continues, the hope of decreasing the gender gap in STEM will be lost. The increase of girls in STEM subjects at the secondary school level can, in the long run, narrow the gender gap in STEM careers.Chapter 6, "The Power in Groups: Using Cluster Analysis to Critically Quantify Women's STEM Enrollment", argues that despite efforts to close the gender gap in STEM, disparities still exist, especially in math-intensive STEM (MISTEM) majors. Females and males receive similar academic support and, overall, perfor...