Throughout my schooling I experienced small class sizes: an average class in my primary school taught 13 pupils, at A Level my largest class was five and my smallest had just two, besides the teacher. Coming to university I have met a host of others who had 30+ in their classes and this led me to think how this difference in education may have affected our learning. Subsequently, I pondered over evidence showing that good teachers make a clear difference in student achievement: the problem we face is that we don’t really know what makes a good teacher. This blog will discuss how class-size reduction (CSR) may affect children’s learning and whether you can define a ‘good’ or ‘bad’ teacher.
Research in the state of Indiana found that students in smaller class sizes scored higher on standardised tests than those in larger classes (Bain & Achilles, 1986); it has also been noted that smaller class sizes reduce behavioural issues and the teachers themselves reported more efficiency and productivity within the classroom. But how effective can these smaller class sizes really be? Bain and Achilles established that smaller class sizes require potentially large scale costs for additional classrooms and teachers, which may be why more schools do not take this approach to learning.
PROJECT STAR: Mosteller began a three-phase project, the first entitled Project STAR (Student-Teacher Achievement Ratio) in 1985, obtaining results from kindergarten, first, second and third grade. Students and teachers were randomly assigned from approximately 80 schools to three different size groups in order to investigate the effect of class size on learning development:
- Small – 13-17
- Regular – 22-25 (with paid aide)
- Regular – 22-25 (no aide)
Curriculum-based tests were used to assess and compare the performance of the 6,500 students. The results showed a substantial improvement in early learning and cognitive studies in those smaller class sizes. Interestingly, the initial achievement of pupils from minority groups was double that of the majority children, however this levelled out in later years as the majority group caught up.
LASTING BENEFITS STUDY: Four years later Mosteller (1989) began the second phase of the study, observing the progressive performance of the children when they were returned to regular sizes. Students who were originally enrolled in the smaller class sizes continued to perform better than those who had experienced larger classes.
PROJECT CHALLENGE: The third and final phase of the project funded 17 of the economically poorest school districts to provide smaller class sizes for kindergarten, first, second and third grades. Their mathematics and reading end-of-year standing from within 139 districts was improved from below average to above average.
Given that most teachers are trained to teach in larger classes of children, Stecher et al. (2001) have highlighted the importance of teacher personal development for the successful implementation of CSR.
On the other side of the scale, a meta analysis conducted by Glass and Smith (1979) found that reducing class sizes from 40 pupils to 30, and even to 25 showed little gain in student performance. However reducing it to as little as 15 pupils did yield a higher level of achievement.
It seems clear that class size does affect the performance of students, with smaller class sizes producing higher levels of achievement; however the reduction of such classes must be substantial in order to see such an increase in performance.
WHAT MAKES A GOOD TEACHER: Regarding teacher performance and characteristics, Sanders and colleagues found that the effectiveness of teachers has more of an influence on student achievement than any other schooling factor. The researchers placed the teachers into effectiveness quantiles based on the students’ growth in achievement. Teachers who fell into the first quantile – the least effective teachers – were found to elicit an average of 14 percentile points per year for student gains. The most effective teachers elicited an average 52 percentile points for student gain.
One can see that the teacher you have is incredibly important to your learning; if you have a ‘bad’ teacher for a subject you do not like, then you are less likely to succeed in that subject than if you had a ‘good’ teacher. However, you cannot choose your teacher and while good teaching is important, it is not clear what makes for a good teacher. Most measures used by school systems to screen candidates for teacher quality look at certification, experience and education level, however there is little definitive evidence to suggest that these characteristics are associated with higher student achievement (Goldhaber, 2002). There is some evidence that experienced teachers are more effective with students, (Darling-Hammond, 1999) but the benefits of additional years of experience appear to level off early in a teacher’s career. Measures of teachers’ academic skills, such as their verbal ability (Peterson, Marx & Clark, 1978), may more accurately predict their effectiveness, but there is far less evidence on this issue, and these findings are also not conclusive.
Interestingly, the effects of a teacher’s quality persists for years after the student has a particular teacher which could either be detrimental or beneficial, depending on which teacher you get stuck with!
Bringing these two topics together, one can see that a large class size coupled with a bad teacher can create a negative learning environment, compared with a smaller class size and a good teacher.
Below is my corresponding talk: