Short synopsis:

Aoshidan kindergarten principal bought a tank, but there's no fuel, and they need to get it to the kindergarten.

El is scared that they'll have to pull the tank, but the principal allays their worries, saying there's no way they'll be pulling it... because they'll be pushing it.

That's a Panzerkampfwagen II Ausf. L "Luchs". It's weight is only 11,8 t.

sanitaeter said:

That's a Panzerkampfwagen II Ausf. L "Luchs". It's weight is only 11,8 t.

'only' 11.8 t

Assuming the principal pulls his weight equal to the 6-year old girls, it's only about 3 tons per girl.
So no complaining and more pushing.