Pietrini Elementary School students Jazmine Lopez (left) and Ema Karajic collaborate to plot a picture graph. | Kevin Tanaka~for Sun-Times Media

Angelina Burciaga is a little stressed about the data for her picture graph in math class at Pietrini Elementary School in Franklin Park. | Kevin Tanaka~for Sun-Times Media

Third-grade teacher Kim Vitale shows Pietrini Elementary School students how to collect and organize data.Third-graders at the school have scored 100 percent on the ISAT math portion for the past two years. | Kevin Tanaka~for Sun-Times Media

Jhoseline Lopez works to interpret data into a picture graph in math class at Pietrini Elementary School in Franklin Park. | Kevin Tanaka~for Sun-Times Media

Sergio Rivera (left) and Aury Cervantes exchange picture graphs so they can answer questions about a poll taken in class at Pietrini Elementary School in Franklin Park. | Kevin Tanaka~for Sun-Times Media.

Ema Karajic (left) and Ernad Abdic look at data collected in math class at Pietrini Elementary School in Franklin Park. | Kevin Tanaka~for Sun-Times Media

Pietrini Elementary School third-grade teacher Kim Vitale shows Axel Vazquez (left) and Mihai Lemieux how to collect data for their picture graph. | Kevin Tanaka~for Sun-Times Media

Sergio Rivera fills in a picture graph. Pietreini Elementary School principal Lois Fronczke credits several factors for the school's high ISAT third-grade math scores, including some new approaches in the classroom. | Kevin Tanaka~for Sun-Times Media

Angelina Burciaga may have been a little stressed about her picture graph data, but third-graders overall at Pietrini Elementary School don't need to worry about their ISAT math scores. | Kevin Tanaka~for Sun-Times Media