hacky sacking - A hacky sack is a tiny bag filled with pebbles that you kick

A hacky sack is a tiny bag filled with pebbles that you kick with your feet until you feel like your legs are going to fall off.

At school, I was hacky sacking during class like I was trying to get the teacher to yell at me.

My brother and his friends were hacky sacking in the garage like they were trying to beat the sack to death.

I was hacky sacking in the park like I was trying to get my legs to explode.