Schools in several European countries frequently fail to provide both excellence and equity in mathematics teaching: more than 20% of European students do not reach a minimum level of basic skills in mathematics; only 2%-3% of them reach the highest level of proficiency; and large variations in achievement exist among students within schools, indicating that schools fail to create equitable learning environments for their students (OECD, 2016). Supporting teachers to combat this challenge requires that teachers be afforded curriculum materials that provide specific support and solid guidelines to teach for excellence and equity, as well as professional development (PD) on how to do so.Responding to this dual need, the main goal of the EDUCATE project was to develop, implement, validate, and refine materials for teachers and teacher educators (TEs) that address issues of cognitive activation (CA) and differentiation (DI) in an integrated manner –which was missing from past work attending to either excellence or equity. More crucially, the project aimed at educating teachers to use these materials by engaging them in guided reflection around their practice and to scaffold TEs to offer solid guidance to teachers in doing so.Working in four EU countries (Cyprus, Greece, Ireland, and Portugal) to minimize context dependencies and ensure the transferability of the materials produced, the project unfolded in four phases. In the first, EU/(inter)national policy documents on excellence and equity were reviewed, as well as prior studies on teachers’ needs and challenges when having to teach for both goals. This top-down approach was complemented by a bottom-up approach involving 66 lesson observations of a maximum variation sample of 33 prospective and practising primary or secondary teachers and 66 pre- and post-lesson interviews with them to identify their actual and perceived needs and challenges when having to engage all their students in challenging tasks. In the second phase, building on this needs-assessment analysis, we developed five modules for teachers and five associated modules for TEs, which aimed at helping them effectively deal with the most crucial challenges identified. After being content-validated and pilot-tested, these modules were implemented with 76 primary and secondary teachers (20 prospective and 56 practicing) working in different school settings (including underserved areas). During this third phase, recruited teachers worked in video-club settings through iterative cycles of experimentation with the EDUCATE materials and reflection upon their practice, facilitated by 16 TEs. TE logs (N=96) and teacher reflection cards (N=401), providing feedback on the implementation of the EDUCATE packages, were completed at the end of each video-club session and were used formatively to inform and refine the PD approach offered. In the fourth phase, we examined the effectiveness of the EDUCATE materials and PD approach. Specifically, the videotaped lessons were coded using an observation rubric developed in the third phase, which comprised a set of 35 phase-level and 10 lesson-level codes related to CA, DI and their interplay. By using linear growth models, we explored changes in the instructional quality in the 201 teachers’ videotaped lessons. Written memos of the videotaped video-club meetings (N=107) and end-of-project teacher/focus group interviews (N=76) were analysed following a phenomenological approach and constant comparative method to investigate participants’ experiences, (re)conceptualisations of CA and DI, and enduring challenges. The project culminated by revising the EDUCATE materials based on the lessons learned from this examination and by producing an e-learning course for teachers and TEs, which is hosted on the EDUCATE platform.The key EDUCATE results pertained to (a) producing a validated, effective, and transferable series of self-contained modules for teachers and their accompanying modules for TEs that concurrently attend to CA and DI; (b) identifying what is feasible to expect from teachers at different educational levels (primary vs. secondary) and career stages (prospective vs. practising)—as suggested by the statistically significant changes identified in aspects of teachers’ practice; (c) surfacing ways in which the modules produced and the adopted PD approach scaffolded teachers’ thinking and work around CA and DI; and (d) identifying challenges that teachers encounter as they currently work at both fronts.The project also raised awareness among different policy makers, stakeholders and researchers about the importance of attending to both CA and DI. Because the EDUCATE outputs are open-access and disseminated through several venues, such as the EDUCATE platform (educate-platform.com/) and website (www.ucy.ac.cy/educate/en/), the impact of the project on TEs, teachers, and foremost students—the ultimate recipients of high-quality instruction—is expected to be long term.