I know it may seem like completely superfluous knowledge, but when I examined the barn-busting scene in Lesson zero, I made a few rational inferences and was able to work out a calculation of how much energy Rainbow Dash hits AJ's old barn with.

assuming that Rainbow Dash is 45kg (approximatly 100lbs) and that she begins her dive at what looks to be around 1000m, she doesn't quite sonic rainboom, but gets fast reguardless. she is in her dive for around 5.8 seconds, and her acceleration is close to 57m/s^2.

The final energy output upon the instance of impact with the barn is approximatly 1337.69 mJ.

or roughly 319.7 kg of TNT. sorry, made a gross mistake, I meant that it had the force of 313.4 TONS of TNT.

so now you know