In this pilot study we investigated whether metalinguistic explanations (ME) could help young learners (YL) boost their metalinguistic awareness (MA) and, in turn, improve their accuracy at the time of using two grammatical features. Although previous research has established a positive correlation between MA, metalinguistic knowledge (MK) and better learning outcomes in a foreign language (FL), few interventional studies have been conducted in this regard. Using a pretest/post-test design, an intact classroom (N = 20) of L1 Spanish 10-year-old students of English as a FL (EFL) was divided into an experimental and a control group. First, both groups completed an individual pen-and-paper MA test. Then, they were paired up according to their proficiency level and asked to carry out a dictogloss task, in which they had to negotiate their final written output. Before the post-test phase, the experimental group was asked to engage with a learning sequence of ME concerning two problematic English grammatical features: third person –s and his/her. These explanations also included the definitions of metalinguistic terminology. Additionally, an individual three-step verbal protocol was carried out after the post-tests to triangulate collaborative data. The results showed a moderate effect of the treatment in MA scores. Likewise, ME had a large effect on the use of third person –s during the interaction, as well as a moderate effect on the accurate use of his/her. Also, the treatment group dyads produced significantly more episodes of noticing during the post-test task and at a higher resolution rate than during the pretest stage. These findings support the use of explicit learning devices such as ME with YL of EFL, as they seem to promote MA and increase their accuracy even in input-limited learning conditions.
