Improving the learning experience in STEM programmes: peer learning as a key factor of an integrated approach in large size classes

Since the early 2000s the process of globalisation has shown that countries can be competitive and play a paramount role on the international stage only if their citizens are given the opportunity to build a significant background in science, technology, engineering and mathematics (STEM). Although the labour market has recently been seeking specialists in these fields, the overall number and the percentage of STEM graduates in post-secondary education remain unquestionably low in the developed countries. A critical issue in this regard is that STEM programmes experience a considerable dropout rate in the first years of higher education. With specific reference to academic physics courses, it has been argued that an inadequate preparation and a substandard performance in high school are significant individual factors which may lead undergraduates to attrition, particularly in the case of freshmen in STEM programmes. Another significant element which could adversely affect undergraduates’ learning is the fact that students may have some misconceptions in physics. Furthermore, most academic physics courses are characterised by a pedagogy centred on traditional lectures. As a classic lecture does not seem to perfectly combine with diversified learning modes and backgrounds, this could be the alleged cause of students’ failure to achieve satisfactory learning in university physics courses. Conversely, many studies demonstrate that learning improves if students are actively engaged during their lessons. Furthermore, it has been pointed out that a student-centred pedagogy increases class attendance, learners’ acquisition of expert attitudes towards the discipline, as well as student engagement. Considering these critical issues, three different courses of action characterised my research. Firstly, I inquired into some possible misconceptions in physics among the students enrolled in some STEM faculties of different countries to identify their level of knowledge in physics at the beginning of their academic career. Secondly, I investigated the effectiveness of an introductory academic physics course which was characterised by an untraditional design and the synergistic use of traditional lectures, peer learning and technology in the context of large size classes. Thirdly, I studied the effectiveness of a blended physics refresher course offered to the future Politecnico di Milano freshmen before the beginning of their academic programme. Thought as a welcome session, this course was characterised by the integration of some different pedagogic factors. To achieve the first objective, I carried out a case study, which was developed in the academic year 2018-2019. The possible incorrect conceptions investigated were partly novel, for instance those related to static friction, while others were to a certain degree well known, like those regarding displacement and distance travelled. All these misconceptions pertained to some issues studied at high school and covered in the introductory physics courses at university. I did not select any items from existing concept inventories, but I created an authentic ad hoc multiple-choice questionnaire which was administered to 1,271 learners at the beginning of each physics course involved in the research. The outcomes demonstrate that the students conceptual understanding of these specific physics topics was adversely influenced by misconceptions that are widely spread among learners, regardless of the learners’ country, educational pathway, experience and socio-cultural background, and the physics macro-area to which the topics belong. This was not a foregone conclusion since some incorrect conceptions had not been investigated previously and all the items in the questionnaire were original. Moreover, I inquired into whether to attend a STEM faculty for some months diminishes students’ misconceptions in physics and whether this potential impact is connected up with progress in either learners’ study method, their knowledge or both. Data analysis showed that to cover some physics topics in an academic course, thus improving the student knowledge of them, generated some degree of effectiveness at decreasing the spread of misconceptions and bringing about students learning. It should be emphasised that this result was not something obvious or self-evident, as the misconceptions persistence as well as the ineffectiveness of traditional academic courses are amply documented in the scientific literature. A second step consisted in considering students at the beginning of different terms and comparing their results in those items of the questionnaire which focused on topics already covered at high school, but not yet studied in any academic course. Although to study at university for six months or one year probably plays a part in developing students’ general and integral process of maturation, this attendance did not appear to influence appreciably the evolution of their study method. Not unlike the freshmen at the beginning of their academic career, the learners who attended classes for longer did not actually seem to be able to critically review some physics concepts and topics already studied at high school. Thus, they continued to employ some incorrect frames of mind to interpret the physical reality. As regards the second course of action included in this research project, I conducted a quasi-experiment to investigate the impact of an innovative teaching practice in the context of a physics course that was addressed to a large size classroom. The effectiveness of this intervention, that was implemented in the academic years 2017-2018 and 2018-2019, was compared to an equivalent physics course which adopted a classical teaching design. A multiple-choice test was administered to the learners at the beginning of the course. This allowed me to collect data on the initial level of proficiency in physics of the students that had been previously assigned to the experimental group and the control group and, most importantly, to analyse their possible equivalence in academic performance. Unlike the academic year 2017-2018, the survey that was administered in the following year focused on misconceptions and was planned to be more demanding. At the end of both academic years, a final multiple-choice questionnaire was administered to investigate the effectiveness of the pedagogic strategies enacted in the experimental group and in the control group. Descriptive and inferential statistics were used to analyse the data collected over the course of the two consecutive academic years. Analysis of the results confirmed that the integrated teaching strategy used with the experimental group was effective in facilitating physics learning in a large size format. This pedagogical practice proved to be all the more successful in enhancing student performance than the traditional teaching approach based on academic lectures. Although this methodology seemed to be fruitful in teaching physics topics of different levels of difficulty, the size of the effect tended to be considerably different. In case of easy topics, the size of the effect tended to be huge, whereas it was small in case of more complex topics. Moreover, in addition to the possible correlation that may be drawn between this innovative teaching strategy and the improvements in the learners’ level of knowledge in physics, also the role of the instructors and their contribution to students’ learning may deserve further investigation. This study also identifies a threshold at which learner exposure to peer learning is likely to be effective in large size classes. Although the level of exposure to peer learning seems to be dependent on the complexity of the physics topics covered in class, it seems to correspond to a small percentage of the total hours of the physics course analysed (e.g., 2% - 2.5%). Therefore, the transition of the traditional pedagogic approach towards this innovative methodology would require only a slight adjustment by the instructors who would not need, all in all, to revolutionise their physics course design and their teaching approach. This may be a strong point in favour of the implementation of the integrated teaching approach described in this dissertation. As regards the third course of action included in this research project, I investigated the effectiveness of a physics refresher course which may be considered as a welcome session offered to Politecnico di Milano future freshmen in the academic year 2018-2019. Provided before the beginning of the first academic term, this course was characterised by the use of some different integrated tools like MOOCs, peer learning and online quizzes. After examining the results of the satisfaction survey compiled by 154 participants at the end of the course, I may conclude that the overall physics refresher course as well as the single educational tools, with the partial exception of the online quizzes, are perceived subjectively by the participants as effective and close to their needs and expectations. Furthermore, I analysed the rate of success and the average mark achieved by the students who had attended the welcome session. A comparison of these parameters with the scores achieved by all the other freshmen in their first academic physics final examination seems to suggest a possible correlation between the attendance of the physics refresher course and the freshmen’s better performance. However, this correlation cannot be definitely claimed and proved on the basis of my preliminary analysis, which certainly has to be deepened in future studies.

Fin dai primi anni 2000 il processo di globalizzazione ha mostrato che le nazioni possono essere competitive e giocare un ruolo importante sul palcoscenico internazionale solo se i loro cittadini hanno la possibilità di costruirsi un background culturale significativo nelle cosiddette discipline STEM. Sebbene il mercato del lavoro richieda sempre di più specialisti in questi settori, il numero complessivo e la percentuale di laureati in questi campi rimane largamente insufficiente nei paesi sviluppati. A questo riguardo, un aspetto critico è rappresentato dall’elevato tasso di abbandono che caratterizza le facoltà STEM durante i primi anni di università. Considerando i corsi accademici di fisica, tra i fattori individuali che possono condurre all’abbandono dei percorsi universitari STEM vi sono un inadeguato livello di preparazione raggiunto e prestazioni inferiori a quelle considerate come standard nella scuola superiore. Un ulteriore elemento da considerare è che gli studenti possono evidenziare alcune misconception, cioè concezioni erronee, in fisica, le quali influenzano negativamente il loro successivo processo di apprendimento. Inoltre, molti corsi accademici di fisica sono caratterizzati da una pedagogia centrata sulle lezioni tradizionali, che non sembrano essere così efficaci nel generare apprendimento diffuso, soprattutto nel contesto di classi numerose. Al contrario, molti studi dimostrano che metodologie di insegnamento attive migliorano la frequenza delle lezioni, l’acquisizione di competenze da parte degli studenti e il loro coinvolgimento. Tenendo in considerazione questi elementi, la mia ricerca si è sviluppata lungo tre diverse linee di azione. In primo luogo, ho indagato l’eventuale presenza di alcune misconception in fisica tra gli studenti immatricolati in facoltà STEM, appartenenti a diversi paesi del mondo. In secondo luogo, ho studiato l’efficacia di un corso universitario di fisica caratterizzato da una metodologia didattica innovativa, basata sull’impiego sinergico di lezioni tradizionali, peer learning (apprendimento tra pari) e tecnologia nel contesto di classi numerose. Infine, ho analizzato l’efficacia di un corso di ripasso di fisica, erogato in modalità blended e offerto a tutte le future matricole del Politecnico di Milano, immediatamente prima dell’inizio della loro esperienza universitaria. Pensato come una sessione di benvenuto (welcome session), tale corso è caratterizzato dall’integrazione di diversi fattori pedagogici. Con riferimento alla prima linea di azione, ho implementato uno studio di caso che si è sviluppato durante l’anno accademico 2018-2019. Alcune delle possibili concezioni errate indagate, quali quelle relative per esempio all’attrito statico, sono nuove, mentre altre sono già note, come quelle riguardanti i concetti di spostamento e di spazio percorso. Tutte queste possibili misconception, comunque, hanno la caratteristica di riguardare contenuti già studiati alla scuola superiore nei corsi di fisica e, contemporaneamente, di essere oggetto di insegnamento durante i corsi introduttivi accademici di fisica. Per la mia ricerca non ho utilizzato test già esistenti, ma ho creato un test originale che è stato somministrato a 1271 studenti all’inizio del loro corso accademico di fisica. L’analisi dei risultati ha mostrato che quelle investigate possono essere classificate come misconception e appaiono essere largamente diffuse tra gli studenti, indipendentemente dal paese e dall’università nella quale studiano, dal loro percorso educativo, dalle esperienze e dal retroterra socio-culturale che li caratterizza, o dalla macro-area di fisica alla quale tali concezioni sono riconducibili. Per quanto riguarda la seconda linea di azione, ho sviluppato un quasi-esperimento per indagare l’impatto di una metodologia didattica innovativa nell’ambito di un corso universitario di fisica nel contesto di una classe numerosa. La ricerca si è sviluppata negli anni accademici 2017-2018 e 2018-2019 e ha consentito di confrontare i risultati ottenuti dal gruppo di studio e da un gruppo di controllo, che è stato esposto a una didattica tradizionale. La ricerca ha evidenziato che tale metodologia innovativa è efficace rispetto all’apprendimento della fisica ed è più efficace rispetto a una didattica tradizionale, indipendentemente dal livello di difficoltà dei contenuti affrontati. Inoltre, la soglia di esposizione al peer learning affinché tale metodo abbia efficacia appare essere piuttosto ridotta. Infine, ho investigato l’efficacia di un corso di ripasso offerto a tutte le future matricole del Politecnico di Milano prima dell’inizio dell’anno accademico 2018-2019. Questo corso, erogato in modalità blended, è caratterizzato dall’impiego di diversi fattori pedagogici, quali MOOC, peer learning e quiz online. Attraverso un questionario di soddisfazione compilato al termine del corso da 154 partecipanti è emerso che questo corso sembra rispondere alle esigenze di apprendimento delle future matricole. Tale risultato sembra essere corroborato dal confronto dei risultati ottenuti da tali studenti nell’esame finale del loro primo corso accademico di fisica con quelli di tutte le altre matricole del Politecnico nello stesso esame. Tuttavia, un’indagine più approfondita deve essere implementata per potere confermare tale risultato preliminare.