When considering the pathway to meaningful integration of technology in education process, two frameworks are insightful, offering as well useful landmarks for continuous professional development: SAMR and TPACK and. SAMR evaluates levels of technology integration, while TPACK focuses on teachers' technological, pedagogical, and content knowledge. Studies have shown that these models can effectively guide technology implementation in various educational contexts.

The SAMR model, proposed by Ruben Puentedura in 2010, provides a framework for teachers to reflect on how they integrate technology into their practice (Puentedura, 2016), encouraging progression from merely substituting traditional methods to redefining learning experiences through technology. It outlines four levels of online learning, arranged by their complexity and transformative potential: substitution, augmentation, modification, and redefinition. When transitioning to online format, educators often concentrate only on the initial two stages, which involve substituting traditional materials with digital equivalents. This might include converting lessons and worksheets into PDFs for online access or recording lectures on video for asynchronous learning.

The SAMR Model on the use of technology to enhance and to transform teaching.
“Explanation of the SAMR Model” by Lefflerd is licensed under CC-BY-SA-4.0

The modification phase comprises a significant redesign of the task, as the technology allows for substantial changes in how the task is performed. An example would be students collaborating on a shared document in real-time, allowing for immediate feedback and collaborative learning.

At the highest level, technology allows for the creation of new tasks that were previously inconceivable. For example, students could create a multimedia project that includes video, audio, and interactive elements, in an asynchronous collaborative environment, and then share it with a global audience.

The SAMR Model can be mapped onto various educational theories and research methodologies:

• Behaviorism: At the substitution and augmentation levels, technology can be seen as a tool to reinforce learning through repetition and immediate feedback.
• Constructivism: The modification and redefinition levels align with constructivist theories, where learners actively construct knowledge through collaboration and creation.
• Bloom’s taxonomy: The SAMR model can be analysed in relation with Bloom’s Taxonomy, with substitution and augmentation corresponding to lower-order thinking skills (remembering, understanding), and modification and redefinition aligning with higher-order thinking skills (analysing, evaluating, creating).

Research on the SAMR model suggests that effective technology integration requires thoughtful planning and reflection by educators. By progressing through the levels of SAMR, teachers can enhance their pedagogical practices and provide more engaging and meaningful learning experiences for students.

Similarly, the TPACK model (Technological Pedagogical Content Knowledge) is a framework for describing the types of knowledge that teachers need to effectively integrate technology into their teaching practices. It has emerged as a relevant and useful model for understanding the intricate relationships between technology, pedagogy, and content knowledge in the context of education.

TPACK is an extension of Lee Shulman's concept of Pedagogical Content Knowledge (PCK), being introduced by Punya Mishra and Matthew J. Koehler in 2006, to address the increasing role of technology in education. The model is based on the idea that effective technology integration in teaching requires a complex, situated form of knowledge that is context-dependent and involves understanding the dynamic relationships among these components.

The model consists of three primary knowledge domains and four intersecting domains:

1. a) Primary domains:

• Content Knowledge (CK): Subject matter expertise
• Pedagogical Knowledge (PK): Understanding of teaching methods
• Technological Knowledge (TK): Proficiency with relevant technologies

1. b) Intersecting domains:

• Pedagogical Content Knowledge (PCK)
• Technological Content Knowledge (TCK)
• Technological Pedagogical Knowledge (TPK)
• Technological Pedagogical Content Knowledge (TPACK)

TPACK is typically represented as a Venn diagram with three overlapping circles, each representing one of the primary knowledge domains. The intersections of these circles represent the integrated forms of knowledge.

The TPACK model. Reproduced by permission of the publisher (© 2012 by tpack.org)

The TPACK framework serves as a foundational basis for research aimed at enhancing technology integration competencies among teachers, illustrating its relevance in contemporary educational discourse. Employing mixed-method approaches, including surveys and questionnaires to assess teachers' self-reported TPACK, classroom observations to evaluate TPACK in practice, content analysis of lesson plans and teaching materials, and interviews with teachers to explore their decision-making processes, numerous studies have provided evidence for the validity and reliability of TPACK as a construct. For example, Schmidt et al. (2009) developed and validated a survey instrument to measure TPACK, and Archambault and Crippen (2009) applied TPACK to online teaching contexts.

Despite its limitations and critiques, such as (1) difficulty in precisely measuring and distinguishing between the different knowledge domains, (2) challenges in operationalizing the construct for research purposes, and (3) potential oversimplification of the complex nature of teaching with technology, the TPACK model has been used as a useful instrument in different contexts:

• to design and evaluate teacher education programs
• to assess teachers' technology integration skills
• to guide professional development initiatives
• to inform educational technology policies.

Certainly, the practical applications of the TPACK model in education are extensive and varied; the examples on how TPACK is applied in educational settings are edifying regarding its value:

1. Curriculum design and lesson planning. Teachers use TPACK (principles) to create technology-integrated curricula that align content, pedagogy, and technology, ensuring that technology use enhances rather than detracts from learning objectives. In their lesson plans, they efficiently integrate sequences and resources such as interactive timelines, virtual museum tours, and collaborative digital storytelling projects, hands-on experiments, computer simulations, and data analysis software.
2. Adaptive teaching. Teachers use TPACK to make informed decisions about when and how to adapt their use of technology based on student needs and learning contexts (e.g. adjusting the use of online collaboration tools based on students' digital literacy levels and the complexity of the task).
3. Assessment design. Educators apply TPACK when creating technology-enhanced assessments that align with learning objectives and instructional methods. For example, developing a project-based assessment that requires students to create multimedia presentations demonstrating their understanding of complex scientific concepts.
4. Blended and online learning design. TPACK informs the development of blended and fully online courses, ensuring a balance between technological tools, content delivery, and effective teaching strategies. (E.g. designing a flipped classroom model that effectively combines online lectures with in-class problem-solving activities.)
5. Professional development. Ministries, HEIs, training institutions and schools design teacher training programs based on TPACK to improve technology integration skills, approaching each component through courses/ workshop series that focus on subject-specific technology tools and how to effectively incorporate them into existing teaching practices. For pre-service training, the model can help in designing courses that require student teachers to create and implement technology-enhanced lesson plans in their teaching practice in classrooms.
6. Teacher evaluation. TPACK can be used as a framework for assessing teachers' effectiveness in integrating technology, by developing, for example, observation rubrics that include criteria for appropriate technology use in relation to content and teaching methods.
7. Educational technology selection. TPACK guides the process of choosing educational technologies that best support specific content areas and pedagogical approaches.
8. Educational research/ educational policy development. Researchers use TPACK as a theoretical framework for studying the effectiveness of technology integration in various educational contexts (e.g. investigating how different TPACK profiles among teachers correlate with student learning outcomes), using the results to feed the educational policies and for creating standards and guidelines for technology use in schools.

These practical applications demonstrate how TPACK serves as a versatile framework for improving teaching and learning with technology across various aspects of education, and especially for guiding teachers' perspective on digital skills and their value in everyday teaching practice.

However, in the last years, the professional development was benefiting from the expansion of the Internet, leaving no doubt about what the digital environment offers for education. In this regard, three major sources of inspiration are bringing about changes in teaching practice: digital resources, professional virtual learning communities, and online courses.

Digital resources offer rich opportunities for teacher CPD, simultaneously developing subject knowledge, pedagogical skills, and digital competences. Usually residing in curated libraries or referenced by specialised portals, they comprise scientific articles, blogs, websites, open educational resources - OERs, and various types of digital resources for teaching, learning, and assessment, providing teachers with up-to-date information on educational trends, research, and best practices.

The open access movement has dramatically increased teachers' access to current educational research. Platforms like ERIC (Education Resources Information Center), ResearchGate, and Google Scholar provide teachers with free access to a wealth of peer-reviewed studies. This access allows teachers to base their teaching practices on evidence-based research, to understand the theoretical foundations of various pedagogical approaches, and to stay informed about emerging trends and findings in education.

The effective use of these digital resources for CPD requires and continuously support certain skills and approaches:

• Digital curation. Teachers need to develop skills in finding, organizing, and sharing digital resources. Tools like Wakelet or Pinterest can help educators curate and manage their digital resource collections.
• Critical evaluation. With the abundance of online resources, teachers must cultivate strong critical thinking skills to evaluate the quality, relevance, and reliability of digital materials.
• Adaptive expertise. As highlighted by Hatano and Inagaki's concept of adaptive expertise (1986), teachers need to develop the ability to flexibly apply their knowledge in new situations, a skill particularly relevant when working with diverse digital resources.
• Networked learning. The concept of connectivism, as proposed by G. Siemens, emphasizes the importance of building and maintaining a professional learning network (Siemens, 2005). Digital platforms like Twitter (with educational chats) or LinkedIn can facilitate this networked approach to learning.
• Digital citizenship. As teachers engage more deeply with online resources and communities, they need to develop and model good digital citizenship, including understanding copyright, digital etiquette, and online safety.

Professional Virtual Learning Communities (VLC) have emerged as powerful tools for teacher professional development, online spaces where education professionals can connect, share experiences, and collaboratively solve problems. In an increasingly interconnected world, the establishment of professional VLCs allows educators to engage in collaborative learning experiences that enhance their knowledge and instructional practices within their specific contexts, ultimately contributing to more effective teaching strategies tailored to the diverse needs of their students.

According to a study by Trust and Prestridge (2021), participation in VLCs can significantly enhance teachers' professional growth and digital competences, providing opportunities for:

• just-in-time learning – teachers can seek immediate help for classroom challenges;
• diverse perspectives – exposure to a wide range of teaching contexts and methodologies;
• sustained engagement – ongoing professional conversations that extend beyond traditional PD sessions.

The use of technology to create digital spaces for collaborative learning among teachers has been shown to enhance their professional knowledge base and facilitate the development of teaching skills (Kopish & Marques, 2020). In particular, these virtual communities serve as a vital resource for educators who may feel isolated in their teaching environments, offering avenues for the exchange of ideas, resources, and support among peers, thereby fostering a sense of belonging and shared purpose within the profession (Reinman, 2015). Additionally, the flexibility of online platforms enables educators to participate in discussions and collaborate on projects at times that suit their schedules, ensuring that engagement is not hindered by geographical or temporal constraints, thus broadening their professional networks and support systems across diverse educational landscapes (Kowalski et al., 2017).

Not less important, VLCs also foster the development of digital skills as teachers learn to navigate online platforms, share digital resources, and engage in virtual collaboration tools.

Similarly, the rise of online courses and MOOCs has provided teachers with flexible, accessible, and personalized opportunities for professional growth. These courses enable educators to engage with a plethora of resources and expert-led sessions that would otherwise be inaccessible, enriching their professional learning experiences and enabling them to integrate innovative practices into their teaching methodologies. Moreover, the flexibility and convenience of these digital learning platforms allow teachers to balance their professional obligations with personal commitments, ensuring that their professional growth is not hindered by the constraints of time or location (Kowalski et al., 2017).

A meta-analysis by Fishman et al. (2013) compared online and face-to-face professional development, finding that online courses can be equally effective when well-designed. Key benefits include:

1. Self-paced learning: Teachers can engage with material at times that suit their schedules.
2. Scalability: High-quality PD can reach a larger number of educators.
3. Multimodal content: Integration of video, interactive elements, and collaborative tasks.

Focusing on the value of MOOCs for teacher professional development, Vivian et al. (2014) highlighted several other advantages:

1. Access to expertise: Teachers can learn from leading educators and researchers worldwide.
2. Community-building: Global networks of educators form around shared interests.
3. Experiential learning: Teachers experience online learning firsthand, informing their own practice.

Engaging in online courses and MOOCs also contribute to the development of digital competences by exposing teachers to cutting-edge educational technologies and pedagogical approaches in online environments.

The relationship between digital competences and CPD is bidirectional. As teachers engage in these online professional development opportunities, they naturally enhance their digital skills. Conversely, stronger digital competences enable more effective participation in online CPD activities.

While the potential of online CPD is significant, researchers like Macià and García (2016) have noted challenges such as ensuring sustained participation and transferring online learning to classroom practice. Future research and development in this area may focus on:

• personalization: tailoring online CPD experiences to individual teacher needs and contexts.
• integration: blending online and face-to-face PD for optimal impact.
• assessment: developing effective ways to measure the impact of online CPD on teaching practice and student outcomes.

Nowadays, digital resources, professional virtual learning communities, and online courses play a crucial role in modern teacher CPD, simultaneously developing educators' professional knowledge and digital competences. As the educational landscape continues to evolve, these types of instruments will likely become increasingly central to teacher professional growth and institutional development.