ABSTRACT
As Covid19 Pandemic hit all over the world, Indonesian high schools are struggled to cope with the sudden and forced switch to fully online learning. This study employed an online survey of Indonesian high school students to understand their behaviour in using online learning. The survey gathers data from 462 respondents who resided in 24 provinces. Theory of Planned Behaviour extended with Perceived Risks and Perceived Costs is used as the theoretical framework. Perceived Risks are used to accommodate concerning security-related news that might affect online activities. Perceived Costs is used to address complaints regarding additional financial burden due to fully online learning, namely cost to access and cost to acquire equipment. SmartPLS version3 is used as the main data analysis tools. The result showed that the Theory of Planned Behaviour is indeed able to explain the use of online learning by Indonesian high school students. Perceived Risks are considered as an influence but only have minimal impact. Perceived Costs does not have any influence on online learning. This might be because Indonesian is quick to act and counter the negative impact of the Covid19 Pandemic. One of the Indonesian Government's efforts is to subsidise Internet costs for students and teachers.