Table 2 Findings from semi-structured interviews: main themes, subthemes, and examples of coded extracts.

Curriculum-related barriers

Textbooks contain large number of topics

9

‘The textbooks are overcrowded with of a lot of topics, there is no time to teach these topics in a very good way, no time to use these strategies’ (English Teacher 3)

The topics contained in textbooks are not designed to support the development of the 21^st century skills

8

‘The textbook encourages teacher to use traditional teaching method not these skills, these skills need more activities’ (Math Teacher 7)

Teachers are restricted to textbooks as the only source of instruction

6

‘It is a good idea to make our teaching activities. But we are restricted to the textbooks. I mean the textbooks are the important that we need to follow. It is the prescribed textbooks that we must follow’ (English Teacher 9)

Teacher-related barriers

Teachers’ attitudes toward the 21^st century skills

5

‘These skills are not so important. Covering all the topics is more important than using these skills. I think they are not so important for the students’ (Math Teacher 4)

Teachers’ low competence in how to integrate the 21^st century skills

6

‘Teachers need to be trained to use these strategies. I need training. There should be regular training, so we can use these strategies’ (Math Teacher 2)

Teachers’ fear of being unable to control their classrooms

9

‘These skills are not suitable for my students. The students are not quite. They will make a lot of noise, for example’ (English Teacher 5)

Student-related barriers

Students’ low competence in Mathematics and English

10

‘How to improve these 21^st century skills, when some students did not know writing or even reading and had no simple basic knowledge. Students’ competence is too low, they do not know basic things’ (English Teacher 6)

Large numbers of students in each classroom

12

‘The big problem is the number of students in each classroom. I have 40 students in Second Intermediate Class A. This enforces you not to be creative or use students’ centred activities, you cannot do anything unless you write on the board and make the students copy what you have written’ (English Teacher 1)

Students’ preference for the traditional approach to teaching

5

‘Students have been taught in traditional methods for a long time. They like this. They like me to explain for them and make them understand, they like me to do everything because I make it easy’ (English Teacher 10)

Administration-related barriers

Lack of encouragement from school administration and educational supervisors

8

‘No encouragement from head of school or support, we need support from the head of school’ (Math Teacher 8)

Official assessments used in schools do not support the development of the 21^st century skills

6

‘Assessments we use do not target the skills you mentioned. I mean I cannot assess students on these skills, this is the policy’ (English Teacher 2)