policy documents on teacher training of the European 
Commission  (2007,  2010,  2012a,  2012b,  2012c), 
Caena  (2011a,  2011b),  the  European  Union  (2006, 
2007, 2008, 2009) and other research studies. On the 
base  of  examples  of  the  policy  approaches  used  in 
Europe,  this  document  explores  and  highlights  the 
concepts  of  teacher  competences  and  competence 
frameworks,  discusses  ways  of  development  and 
assessment of teacher competences, and “defines the 
key factors that lie behind successful policies” 
(European  Commission,  2013,  Chapter  5).  The 
document  acknowledged  that  “The process of 
bringing stakeholders together to discuss these issues 
can, in itself, be beneficial, especially if it leads to an 
increased sense of ownership of the results and a 
commitment to their implementation.”  (European 
Commission, 2013, p. 43). 
A  major  study  of  teachers’  related  policy  was 
conducted during the 2002-2004 period by OECD in 
collaboration  with  25  countries  (OECD,  2005), 
aiming to explore, systematise, and present issues and 
effective policies with respect to the activities, related 
to developing effective teachers. Its methodology is 
to  some  extent  similar  to  the  methodology  of  the 
study,  presented  in  this  paper.  It  addresses  4  key 
issues,  related to  the  topic.  The study  methodology 
included  the  preparation  of  countries’  background 
reports  (based  on  a  predefined  set  of  questions  and 
requirements),  organising  workshops  in  different 
countries  and  disseminations  of  their  results, 
implementing  national  visits  of  experts  groups, 
writing  paper  reports  on  the  basis  of  the  different 
visits to detect issues, collecting rich sets of data and 
performing specific data analysis, and describing the 
main results in the policy report (OECD, 2002).  
Another  well-known  initiative  of  OECD  is  the 
Teaching  and  Learning  International  Survey 
(TALIS), a periodic survey, administered in 2008 and 
2013,  and  planned  for  delivery  in  2018.  Bulgaria 
participated in both 2008 and 2013 surveys and will 
participate in the 2018 edition. This gives a very good 
opportunity  for  triangulation  of  the  findings  and 
results of the described by the  current paper STEM 
teachers’  competences  development  study  with  the 
TALIS results for Bulgaria. 
Yet  another  big  OECD  current  initiative  is  the 
Innovative  Teaching  for  Effective  Learning  (ITEL) 
project.  First  an  extensive  research  work  was 
conducted,  resulting  in  a  book  (Guerriero,  2017), 
focussing  on  conceptual  framework  of  teachers’ 
professional  competence,  where  the  teachers’ 
competence  is  fed  by  the  initial,  continuous,  and 
informal/non-formal  teacher  learning,  consists  of 
content  &  pedagogical  knowledge  and  affective-
motivational competences and beliefs, and results in 
teaching  approaches,  which  lead  to  instruction  that 
supports  the  cognitive  and  social-emotional  student 
learning  (Guerriero,  p.  261).  This  competence 
framework  was  used  for  the  development  of  the 
survey  instruments  of  international  comparative 
studies conducted in ITEL that investigate teachers’ 
knowledge  as  a  key  component  of  teacher  quality 
(Sonmark et al.). 
There is a big number of other studies that focus 
explicitly on the teaching-related factors, which play 
as stimuli or barriers to inquiry-based learning (IBL). 
For example, Kang and Keinonen, (2016) commented 
the  results  of  7  small  scale  studies,  conducted  in 
different  single  countries,  and  summarised  that  the 
reported  in  these  studies  barriers  and  teacher 
reluctance to apply IBL may have as main inhibiting 
factors: the low teacher confidence and competence 
in  using  inquiry  instructions;  the  lack  of  time  and 
resources;  the  tight  curricula;  the  inadequate 
professional  development;  the  large  class  sizes,  the 
lack of professional science content knowledge; the 
difficulties  in  developing  students’  ideas  and  in 
designing experiments for students’ hypotheses; and 
the  insufficient  school  resources  (Kang  and 
Keinonen, p. 32). Authors pointed out the “teachers’ 
confidence in teaching science and their collaboration 
to improve science teaching” as important factors for 
implementing  IBL  (Kang  and  Keinonen,  p.  44).  In 
another  study  of  34  IBL  early-adopting  Australian 
teachers, the participating teachers pointed out as the 
most important barriers to IBL-teaching “the extreme 
time restrictions on all scales, the poverty of their 
common professional development experiences, their 
lack of good models and definitions for what inquiry-
based teaching actually is, and the lack of good 
resources enabling the capacity for change.” 
(Fitzgerald et al.). 
In  a  successful  effort  to  cope  with  the  counted 
above  barriers,  the  IBL-in-Science  focused  EC 
project  “weSPOT”  formulated  prerequisites  for 
successful IBL in schools, based on earlier research 
results,  namely:  “change teachers’ attitude and 
provide stronger support to students (at micro level); 
provide schools management support; enable 
teachers to share experience and best practices; 
provide the needed ICT support (at mezzo level); 
provide constant training for teachers and a rich set 
of resources based on ICT infrastructure (at macro 
level).”  (Nikolova  and  Stefanova).  The  weSPOT 
researchers  then  developed  a  reference  model  for 
inquiry skills, and a diagnostic instrument to measure 
the individual performance  on inquiry skills. In  this 
way the project “
provided teachers and learners with