The COVID 19 pandemic heavily affected the education system regardless of grade level.

 All over the world, the main effect of the pandemic at the level of Higher Education was to trigger a transition from on-site classes to online classes or an hybrid system.

 ISEG, as all schools in the country, switched from on-site classes to online ones. Teachers and students had to adapt to this huge change in teaching and learning methods in just a week.

 Teachers had to change the way they are used to teaching. Although most students have computers, internet connection problems made it difficult to follow online classes. Furthermore, despite teachers’ great efforts to reinforce mentoring, the lack of face to face contact between teachers and students made teaching and learning a much greater challenge.

 Students’ evaluation also changed from on-site to online which was new to both teachers and students.

 These conditions held for Summer semester of 2019/2020. For the Fall semester 2020/2021, we had an hybrid system. Lectures were online, but practical classes were hybrid, with half of the students physically attending one week and the other half the next. Students not physically in the class could join it online. Sound and image were recorded in on-site classes.  

In this paper we go beyond what most of the studies did, since we compare the students’ academic performance in the three scenarios on-site, online only and hybrid. We analyze the students' perceptions regarding the move from on-site to online or mixed education.

 Our main research questions are:

-          How did students feel about the changes above mentioned?

-          What are students´ perceptions about the way the changes affected their learning?

-          How did the above mentioned changes affect students’ academic performance measured by their marks at the end of each of the semesters above mentioned?

-          Do individual and family background characteristics have any impact on students’ perceptions and their academic performance within this pandemic situation?

 Numerous studies have been emerging since the summer semester of 2019/20 on the effects of the pandemic on HE students. Most of these studies concern practical cases, related to the situation experienced in a given institution or comparisons between HE institutions regarding changes in teaching methodologies due to the pandemic. Some of them, provide a first overview on a large number of countries and are based on surveys directed at students on the assessment of the transition to online or mixed study (Aristovnik et al 2020; Crawford et Al 2020; Li & Lalani 2020; Vo et al. 2017).

Many of the studies are concerned with students' perceptions and expectations about online teaching in terms of intrinsic motivations. They seek to find out whether learning has become easier and more motivating, requires a larger work load and affected academic performance (Aucejo et al. 2020; Besser et. al 2020; Demuyakor 2020). Another line of research, investigates to what extent the transition to online education aggravates socio-economic inequalities among students (Aucejo et al. op cit ). 

Several studies emphasize the role played by teachers and tutors in extra-class hours, participation in debates and seminars,  features that students consider most successful to develop their sense of belonging (Aristnovik et al, op. cit; Johnson et al 2020).

Another set of studies is concerned with the possible social devaluation of online education compared to face-to-face. Such studies have identified expectations of greater difficulty in obtaining a future job, potentially lower wage levels, among others. (Brammer & Clark 2020; Demuyakor op. cit.).

The results showed a great level of heterogeneity in the perception of the positive and negative aspects of the transition to online education.

In this study, we use databases gathered by our school with data of marks and individual and family background characteristics as well as a survey to our students with questions related to their perceptions. Because it will make this study long and heavy we only took one curricular unit from the areas of Mathematics – Statistics I and II, Economics – Microeconomics I and II, and Management – Cost Accounting and Accounting II, since students have different levels of difficulty learning contents from the three. The marks on these C.U.(s) are the ones stated in the following table: Academic year Semester On-site only Online only Mixed 2018/19 Summer Statistics II Microeconomics II Cost accounting 2019/20 Fall Statistics I Microeconomics I Accounting I 2019/20 Summer Statistics II Microeconomics II Cost accounting 2020/21 Fall Statistics I Microeconomics I Accounting Since we want to acknowledge differences in academic performance due to the changes in teaching and learning during the pandemic, we only deal with students enrolled in 2nd year of the undergraduate curriculum in academic years 2019/20 and 2020/21. We consider that those in the 1st year are still dealing with the struggle of adapting to Higher Education in 2019/2020 and most of those on the 3rd year graduated in 2019/20 and were not students in 2020/21. Because we want to investigate the impact of the pandemic on academic performance we use marks for the C.U.(s) above mentioned. We use parametric tests to test equality of means of marks before and after the pandemic and during the pandemic between fully online and mixed teaching. To determine whether individual and family background characteristics play a role in the way students deal with the pandemic conditions we do Pearson Qui-square tests for independency and multivariate analysis such as Principal Component Analysis. We intend to launch a survey to the students above mentioned in order to assess their perceptions, expectations and motivations towards the change in teaching and evaluation methodology. Our survey is an adapted and reduced version of the one carried out by the European Students Union. The survey has the following blocks of questions: - perceptions about how the change affected teaching, learning and evaluation; - perceptions about how the school and teachers helped, namely through mentoring; - perceptions about family economic and logistic struggles concerning the needs for an online study; - expectations regarding the impact on a future job of the transition to online teaching.

As teachers, we feel the insecurity and unease of our students, so we expect students to feel negatively about the changes, and see these changes as having heavily affected their learning process. We also expect that it had a negative impact on their academic performance.

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