Sounds good. And it is. But. Always a but. They're tricky things.
Getting children blindfolded quickly so the action stays fast-paced is tricky. Getting children to safely wield a big stick is tricky. Getting children to swing a big stick at a swinging object hard enough to break it is tricky. Getting children to wait patiently in a line for their turn, close enough to see what's happening, but far enough out of the way that they don't get clobbered by the swinging stick, is tricky. Getting children to understand that the free-for-all that takes place when the piñata finally breaks still means they should be kind enough to share their giant scooped up hand full with the child next to them that only scored one trod-on yellow banana is tricky. Lastly, getting children to understand back at home that belting the xxx out of something is only considered a funny-game in the most occasional of circumstances is tricky.
That said, Mimi went to a dinosaur-party recently and had her first ever go at a piñata, as pictured above, and she loved it. She only managed to pick up three fully-formed lolly-bananas, but was content to have been part of the action, and admitted she felt sorry for the kids further back in the line that missed out on having a go.
She also let me in on a secret after the party; "I know for sure what happened to the dinosaurs mom and why they're gone now; they all got caught in a giant snowball and it rolled them all away." It's a theory of extinction I haven't heard before. It sounds good. But tricky.