1.
Hydrochloric-Acid-Filled Piñatas

Good: Have the sturdy construction required to ensure no unintended leakage of contents.

Bad: Possible severe burning. Brings the party down.

2.
Endangered-Animal Piñatas

Good: Kids love animals. High potential for very cute-looking piñatas, like baby seals, for instance.

Bad: Beating with a stick sort of sends the wrong message.

3.
Particle-Accelerator Piñatas

Good: Built full-scale and often several miles in dimension. Therefore, young children find them easy to hit.

Bad: Each one worth several billion dollars. Parents generally not keen on damaging them.

4.
Smallpox (Variola major) Piñatas

Good: Cool virus shape.

Bad: Highly contagious and high mortality rate. Would also bring party down—as well as everyone else within a 100-mile radius.

5.
Infinity-Symbol Piñatas

Good: Possibly a way to address the often reported decline of mathematics education.

Bad: Thinking about infinity makes my head hurt. Now imagine having to explain it to a child over and over again.

6.
Piñatas in the Shape of the USA and Filled
With the Greenhouse Gas Carbon Dioxide

Good: Sort of work as a metaphor for the United States’ role in the global-warming crisis.

Bad: Unfortunately, the irony would be totally wasted on a 5-year-old.