Fredericton high school students missed out on a lesson in democracy by not being able to attend a rally by Liberal leadership candidate Justin Trudeau, says UNB professor Alan Sears. (CBC)

Students missed a good learning opportunity at a campaign stop by federal Liberal leadership candidate Justin Trudeau, says an education professor from the University of New Brunswick.

'We want to teach kids to identify bias or prejudice or even more nasty things like racism or sexism in material. It doesn't mean we're promoting it."—Alan Sears, UNB education professor

A field trip to see Trudeau by Grade 12 political science students at Fredericton-area high schools last week was cancelled by the district superintendant because of fears it could be seen as partisan.

"But our democratic system is partisan and adversarial by nature and students need to see and experience that, with the guidance of a good teacher" UNB professor Alan Sears said.

"We want to teach kids to be able to identify bias or prejudice or even more nasty things like racism or sexism in material. That means we have to actually show students what it looks like. It doesn't mean we're promoting it," Sears said.

However, Sears applauds Anglophone District West superintendent David McTimoney for going into classrooms to personally explain his decision to students.

That in itself was a good lesson in civics, said Sears.

"We often use school children in covert partisan ways. When we have politicians come to a school and read to kids, we take their picture. I understand that sometimes they're making an official announcement, but they're also using that as partisan fodder to say, 'I'm a nice person. I like kids. Vote for me.'"