 Balliett used art and blank plates as inspiration for the characters ' names . Calder Pillay is derived from the artist Alexander Calder and Petra Andalee was inspired by the architecture in Petra , Jordan . The names were meant to be different , which Balliett considered " fun for a child . " Balliett felt that she could capture the attention of reluctant readers if they related to characters who enjoyed writing and math . Calder and Petra 's teacher , Ms. Hussey , was inspired by an old name on Nantucket Island and the old @-@ fashioned word hussy . Balliett compares herself to Ms. Hussey , stating that " [ we ] think a lot alike . " Some of Ms. Hussey 's assignments and dialogue even came from Balliett 's classroom . She chose the setting of Hyde Park , Chicago , where she currently lives , because she considered it full of secrets that children could discover . 
 Balliett used art and blank plates as inspiration for the characters <a href='null_genetive' title='1'><mark>'</mark></a>names . Calder Pillay is derived from the artist Alexander Calder and Petra Andalee was inspired by the architecture in Petra , Jordan . The names <a href='uninflect' title='2'><mark>were</mark></a> meant to be different , which Balliett considered " fun for a child . " Balliett felt that she could capture the attention of reluctant readers if they related to characters <a href='null_relcl' title='3'><mark>who</mark></a>enjoyed writing and math . Calder and Petra <a href='null_genetive' title='4'><mark>'s</mark></a>teacher , Ms. Hussey , was inspired by an old name on Nantucket Island and the old @-@ fashioned word hussy . Balliett <a href='uninflect' title='5'><mark>compares</mark></a> herself to Ms. Hussey , stating that " [ we ] think a lot alike . " Some of Ms. Hussey <a href='null_genetive' title='6'><mark>'s</mark></a>assignments and dialogue even came from Balliett <a href='null_genetive' title='7'><mark>'s</mark></a>classroom . She chose the setting of Hyde Park , Chicago , where she currently <a href='uninflect' title='8'><mark>lives</mark></a> , because she considered it full of secrets that children could discover . 
Balliett used art and blank plates as inspiration for da characters  names . Calder Pillay is derived from the artist Alexander Calder and Petra Andalee was inspired by the architecture in Petra , Jordan . The names was meant to b different , which Balliett considered " fun fir a child . " Balliett felt dat she could capture the attention of reluctant readers if they related to characters enjoyed writing and math . Calder and Petra  teacher , Ms. Hussey , was inspired by an old name on Nantucket Island and the old @-@ fashioned word hussy . Balliett compare herself to Ms. Hussey , stating tdat" [ we ] think a lot alike . " Some of Ms. Hussey  assignments and dialogue even came from Balliett  classroom . She chose tdasetting of Hyde Park , Chicago , where she currently live , because she considered it full of secrets thdathildren could discover .