Potion
The potion is perhaps a nod to the creativity of young people. It can also be a reference to designing medicines and treatment to solve global matters, such as poverty.
Grandmother
The grandmother is portrayed as a bully and a nuisance. She could symbolize the adversity that children may face from those older than them.
George as the Underdog
George is a symbol for the underdog. He went from being bullied by his grandmother to getting the upper hand and making his bully disappear from his life forever