I went to a Catholic school in the 1960s, so it goes without saying that my sex education consisted of puzzled playground discussions and furtive looks at Playboy magazines.

I wonder what the nuns at my school would have made of the explicit little pamphlet that turned up at a Grade 8 sex-education class in Nanaimo, on Vancouver Island.

A flipbook (you riffle the pages with your fingers to create a moving image) entitled Put on Something Sexy that depicts a woman putting a condom on her lover's erect penis, after which the naked couple make love, was made available at the Jan. 31 class in Wellington Secondary School, the National Post reported.

The flip book, whose pages can be viewed here, apparently was given to a boy as a prize in the Grade 8 sexual-health class (I wonder what he had to do to win it).

When the parents of the 13-year-old saw the pamphlet they hit the roof.

[ Related: Graphic sexual education flipbook angers B.C. mom ]

“I was physically nauseous when I saw what they had given to him,” mother Cathy Sanders told CTV News.

The boy's father, Clay Sanders, said the flipbook was "cartoon pornography."

“I don’t think any depictions of sexual activity are necessary to pass on to children in school,” he told CTV News.

Officials of the Nanaimo-Ladysmith school district quickly apologized, sending a letter to parents of students who'd attended the session. Spokeswoman Donna Reimer said AIDS Vancouver Island had provided the booklet, which had not been approved beforehand.

“When the school discovered the material they realized it was inappropriate and they removed it,” Reimer told CTV News.

But AIDS Vancouver Island, which has been involved in student education for 15 years, defended its use of the flipbook, saying it's been featured in many classes previously without incident.

“Providing students with straightforward, non-judgmental information about safer sex and sexuality is critical to making sure that those students know how to protect themselves against not only HIV but also a host of other sexually transmitted infections,” spokesman Eric Berndt told CTV News.

Reimer told the Daily News AIDS Vancouver had put material on a display table for students to look at. One pamphlet explaining oral sex was removed when an administrator spotted it.

In future, all materials will be reviewed by the school district before being used in sex-ed classes, she said.

Cathy Sanders said she worried her son had been traumatized by the flipbook.

"Once a child is exposed to something, you can never erase that from their memory," she said.

Make of that comment what you will, but the incident does raise questions about age-appropriate materials.

[ Related: Sex education delays teen sex, study finds ]

School sex education has always met resistance from some parents who see the facts-of-life talk to be their job. If schools want a role, parents must be allies. There has to be a balance between being explicit enough to get the message across and without being so graphic you risk a parental backlash.

The web site About Kids Health, administered by Toronto's Hospital for Sick Children, offers some guidelines about what's appropriate to discuss at particular phases of childhood. It notes teens tend to be more private about these things, which makes an early discussion about sexual basics and safer sex essential.

B.C. mom outraged after son brings home graphic sexual flipbook from school