Tara's sister pays the sales tax on the t-shirt kit Tara has been saving for, on the condition that Tara give her ten cents every time she uses something that taxes pay for.
Lucy wants to make Mother's Day special, avoiding the disasters she usually creates, so she works with her neighbor, Diego, to celebrate the holiday as it is done in Mexico.
With his mother away on a business trip, Ravi is afraid his birthday will be boring until a mysterious clue starts him on a treasure hunt that takes him all over town.
Amy, desperate to get her hands on the latest video game, learns how people acquired things before money existed, and decides to take a lesson from history.