“…Nevertheless, divided arguments regarding problem-based learning are found. Some studies found the strengths of problem-based learning for enhancing students' 21 st -century skills (Anazifa & Djukri, 2017;Bashith & Amin, 2017;Duff, 2008;Ghufron & Ermawati, 2018;Hadi & Izzah, 2018;Iswandari et al, 2017;Lapuz & Fulgencio, 2020;Keong & Mohammed, 2015;Munawaroh, 2020;Yuberti et al, 2019). On the other hand, some studies found the complexity and challenges in implementing problem-based learning (Blundell & Berardi, 2016;Ceker & Ozdamli, 2016;Ghufron & Ermawati, 2018;Iswandari et al, 2017;Kassem, 2018;Miner-Romanoff, Rae, & Zakrzewki, 2019).…”