Explicit vocabulary learning is a burden for most of the students. But vocabulary is the basis of each language, and not all words can be acquired incidentally through context or reading. Especially for content and language integrated learning in L2 it is important to offer lots of support for learning a large number of terms in order to avoid frustration and negative impact on motivation for the subject. This classroom study investigated the effects of odor on L2 vocabulary learning. The olfactory sense is connected with the limbic system and therefore associated with emotions and motivation. Young EFL Learners (n=158) were randomized to 7 different groups to compare the effects on retention of vocabulary, on motivation and concentration. A mix of essential oils that is proven to enhance concentration and vigilance was given as support. Major finding found as a result of the testing was the positive correlation with the time during a school day the odor was offered as support.