Experimental Design
Our randomized controlled trial (RCT) focuses on Flemish primary school students (i.e. ages between 6 and 12 years old), with part of the analysis diving deeper into the sub-group of students coming from more disadvantaged backgrounds. In particular, we focus on primary school students due to the existing evidence that both COVID-19 and summer-related learning losses have disproportionately impacted younger students. The experiment will be carried out through a pre- and post-test strategy. The survey has been made in such a way that it is adapted for the younger audience within our population of interest, meaning that older subjects should not have any problem responding to it. The use of the same questionnaire is important for comparison purposes among individuals of different school grades.
In the last few weeks of the school year 2023/24, we have surveyed participants, gathering information on the students' demographic characteristics, mathematical cognitive ability, linguistic cognitive ability, socio-emotional state, previous partaking in summer schools or similar programs, opinion about their school, teachers and classmates, as well as expectations for the next academic year. The survey was divided into three parts. During the first part, students responded for the first time to the aforementioned set of questions. During the second part, students were exposed to a small prompt with images that varied according to their assignment to a control or treatment group, with treatment being randomly assigned at the student level using the randomization tool incorporated in the survey platform. Finally, students were asked a reduced number of questions intended to assess their attention during the treatment moment, followed by a repetition of a portion of the questions shown before the informational prompts, which was our way of assessing the effect of our treatment. Furthermore, questions aiming to grasp the individual's cognitive ability were conditional on the grade they were attending at school, at the moment of data collection.
Students were randomly assigned into five groups: control; treatment 1, which looked at the role of students' anchors tied to their opinions about their school; treatment 2, which was focused on the effect of our nudging strategy; treatment 3, which put together treatments 1 and 2; and treatment 4, which showed students how school can help them improve their socio-emotional state. The control group was exposed to no informational prompt at all. Those in treatment 1 were exposed to information on how school can help students learn better and how schools can be beneficial to them. Students assigned to treatment group 1 were exposed to a set of statements that shed a positive light on school as well, in an attempt to contradict this possible negative anchor. Those in treatment 2 were exposed to information about what are summer schools, what kinds of activities take place in them, the benefits of participating in summer schools, as well as some examples of alternative ways of spending their summer. Those in treatment 3 were exposed to all the information in both treatments 1 and 2. Finally, those in treatment group 4 were shown a series of socio-emotional statements tied to an explanation of how schools and summer schools can help develop those skills. Additionally, all students responded to a couple of questions intended to test their propensity for anchoring bias in the traditional sense (based on definition by Tversky and Kahneman, 1974), followed by a question on their opinion about their school, the treatment, and only then an inquiry concerning their likelihood of participation in a summer school program, which should allow us to capture the immediate effect of treatment 1. The test concerning their propensity for anchoring bias was designed such that students were shown a list of 15 simple pairs or words, they answered a couple of other questions (e.g. about their previous experiences over the summer), they were exposed to the question assigning them to a treatment group, and they were asked to state how many pairs of words they thought they could remember, in this order. Administrative data and data on the media campaign for summer schools served as supporting materials for our main research purpose as described above.