> is there a correlation between academic performance and classroom laptops?

Yes, here is Dr. Horvath's (the neuroscientist mentioned in the article) written testimony which cites some studies.

The table in Section 3 is particularly damning. It shows how a classroom intervention worsened or improved outcomes relative to the baseline. Note that the worst intervention is the "1-to-1 laptops row".

Unclear if they mixed interventions, I'd have to read the mentioned studies. If the interventions were done in isolation then that's basically a longitudinal study which is a pretty clear smoking gun.

https://www.commerce.senate.gov/services/files/A19DF2E8-3C69...