Influences of learning according to Hattie's research

It is important to look at the research results in light of the barometer of influence:

You know it's making an impact from 0.4 to 1.2.
Many of our educational interventions have a low impact of 0.2 to 0.4.
Considering that inordinate amounts of money, resources and time are used to yield an effect size of 0.2, it would be better to simply allow a child to develop normally and the effect would be 0 to 0.2!
Even worse, what about the interventions that have a negative effect? From -0.2 to 0? They actually have a reverse effect on learning! Summer vacation, television and retention are the BIG losers.

With this in mind, consider some of the following findings: