Two Teachers in the class

Investigating the effect of an increased teacher-pupil ratio.

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two teachers

Location: Hordaland, Rogaland, Vest-Agder, Aust-Agder, Østfold, Vestfold, Buskerud, Oppland og Akershus 

Sample: 5750 children in 300 classes and 150 schools in 9 Southern Norwegian counties.

Timeline: 2016 to 2033

Target group: Students from Grade 1 to the end of high school.

Outcome of interest: Reading achievement, motivation for reading and classroom climate.  Long-term achievements in school.

Intervention: An additional teacher in Norwegian lessons in  Grades 1 and 2. Professional development for teachers in literacy instruction.

AEA RCT Registration number: AEARCTR-0002242

Data: Achievements in emergent literacy skills pre-intervention, Achievements in reading, spelling, literacy motivation and classroom climate post-intervention, and in a one-year follow up. Registry data on family background and school achievement.

Principal investigators: Oddny Judith Solheim, Mari Rege and Erin McTigue

Investigators: Oddny Judith Solheim, Njål Foldnes, Bjarte Furnes, Aslaug Fodstad Gourvennec, Venke Furre Haaland, Ella Cosmovici Idsøe, Maria Therese Jensen, Marja-Kristiina Lerkkanen, Kjersti Lundetræ, Erin McTigue, Mari Rege, Knut Schwippert, Atle Skaftun, Per Henning Uppstad, Åse Kari Hansen Wagner

Funders: LÆREEFFEKT – Norwegian research council

Two teachers in the class is a group randomized controlled trial investigating individual and complementary effects of teacher-student ratio and professional development for teachers.

It seems evident that by increasing opportunities for individualized support, a higher teacher-student ratio could increase student learning. However, the empirical evidence on teacher-student ratio is mixed. In fact, several studies conclude that there are no effects of teacher-student ratio on student achievements.

Two teachers in the class seeks to investigate effects of increased teacher-student ratio, effects of professional development for teachers, and complementary effects of a professional development and increased teacher-student ratio.

We have 150 schools, with two classes at each school, participating in the trial. We vary treatment in two tiers: In the first tier, we randomly assigned one incoming class as treatment and one as control. The treatment class received an additional teacher in Norwegian lessons, 8 x 45 minutes a week for 38 weeks, in Grade 1 and 2. The control class received no additional resources, but we assess student achievements and motivation in the same way as in the treatment class. In the second tier, we randomly choose 50 schools to adapt to a program for professional development in literacy instruction (Language Track) (Condition 1), and 50 schools to adapt the Language Track Program with additional instructions for how to use the extra teacher in the treated class (Condition 2). The remaining 50 schools were not asked to change their instructional approach, thus creating a “business as usual” situation (Condition 0) (see also Solheim, Rege & McTigue, 2017).

The two-tiered design allows us to investigate effects of increased teacher-student ratio, effects of professional development, and importantly: complementary effects of these two treatments.

We do all effect analyses on the following domains of measures:

 (i) Students achievement in word reading, reading comprehension and spelling

 (ii) Students’ literacy interest, reader self-concept and achievement strategies

 (iii) Classroom climate and emotional support

 (iv) Teaching practices in literacy instruction.

Read more about Two Teachers:

Norwegian Centre for Reading Education and Research
Norwegian Research Council

About Synapse Lab

UiS Synapse Lab develops and investigates interventions for promoting motivation and learning in education and work life. The fields of the most active researchers in the Lab are education, economics of education, labor economics, psychology and public health. In most of our research projects, we work across disciplines.