<p style="text-align: justify;">The pandemic case has shifted away from face-to-face teaching to online blended learning. This phenomenon certainly causes various problems in the world of education. The online blended learning is good when applied with good internet connections and complete facilities. However, it differs from Indonesian coastal students who do not have supporting facilities. Therefore, this research aims to analyze the experience and readiness of Indonesian coastal students. It determines the facilities of the process using qualitative research with a phenomenological approach. Purposive sampling was used to collect data from 25 students living in coastal areas in Aceh, Indonesia. Furthermore, in-depth interviews were used to obtain instruments and techniques for data collection, observations, field notes, and audio-visuals. Data analysis was carried out qualitatively by reducing, displaying, drawing conclusions, and verifying data. The data processing was conducted using NVivo 12 plus software. The kappa coefficient is used to check the accuracy of the data since there was no bias during coding. The analysis results show that Indonesian coastal students are not ready to conduct the online blended learning process. Furthermore, it is recommended that future research focus on coastal students’ development. A Hypothetical Learning Trajectory design should be created to assist in independent learning and lessen their readiness.</p>

Problem-based learning (PBL) is considered to improve students' critical thinking (CT) skills. However, there are several obstacles to implementing this instructional model. PBL is highly time-consuming and creates a high cognitive load, so it is not suitable for all students, especially students with low prior knowledge. To investigate this problem, we conducted a quasi-experiment to study the difference in the improvement of CT skills between students who study using PBL and student who study using PBL with problem posing within-solution (PPWS). The sample of this research is 71 high school students in Mataram City. The result revealed that there was no difference in the enhancement of CT skill between students who learn using PBL and student who learn using PBL with PPWS. This means we can substitute PBL into PBL with PPWS to foster student CT skills.