For young learners of English as a foreign language (EFL), the initial acquisition of English vocabulary is crucial to English proficiency. This study conducted a systematic review of studies of primary school students' EFL vocabulary learning to identify types of activities for learning new vocabulary. A total of 57 vocabulary learning activities from 22 studies were coded, yielding ten types of intentional and eight types of incidental learning activities. The intentional learning activities involved more psychological conditions than the incidental ones. Following the involvement load hypothesis (ILH), we identified activities encompassing various combinations of psychological conditions inducing the highest and lowest involvement loads (ILs); the more such conditions an activity encompasses, the deeper the vocabulary learning processes, and the higher the IL, the better the retention. The comparison between the activity types provides useful information for teachers and researchers to design age-appropriate English vocabulary learning activities.