Evidence-based strategies are strategies, practices, or programs (referred to more broadly in ESSA as “interventions”) that have solid evidence to show that they produce results and improve outcomes. They’ve been tested, and they’re based on knowledge gained through rigorous research.
The School-based Mental Health Grant requires that grant-funded activities must meet either the ESSA Tier 1 Strong Evidence or Tier 2 Moderate Evidence Level:

Tier 1 Strong Evidence
A practice, strategy or program is considered to have strong evidence of its effectiveness if it is backed by a randomized control experimental study that has all of the additional indicators of quality and relevance.

Tier 2 Moderate Evidence
A practice, strategy, or program is considered to have moderate evidence of its effectiveness if it is backed by a quasi-experimental study that has all of the additional indicators of quality and relevance.