The dissemination of good practices in MLE requires a more rigorous definition of their characteristics, including criteria and indicators to measure their quality. This article -- after reflecting on the meaning and function of identifying good MLE practices -- presents a systematic framework of 35 indicators for good MLE activities in Italian elementary schools. These indicators are grouped according to five general criteria of quality: adequacy of the teaching methods; competence and involvement of the actors; structuring and coherence of the activity's organization; awareness of the underlying MLE theories as well as their appropriateness; and originality of the project. The framework emerged from a four-level process, which is also presented in the article: Based on an initial review of features attributed to quality MLE in scientific and institutional literature, a preliminary draft of criteria was elaborated and submitted to scholars and experienced teachers, whose comments were sought in semi-structured interviews. This input fed into the final version of the framework, which may serve to support teacher trainings as well as the monitoring and (self-)evaluation of teachers' MLE work.