The following hypotheses of the research are applied to guide the investigation.
Ho1: Mathayom Suksa 3 students’ science vocabulary retention is not promoted after learning through a world café activity.
Ha 1 : Mathayom Suksa 3 students’ science vocabulary retention is promoted after learning through a world café activity.
Ho 2 : ODI has no initial impact on Mathayom Suksa 3 students’ science vocabulary retention.
Ha 2 : ODI has the initial impact on Mathayom Suksa 3 students’ science vocabulary retention.