A new report finds that fewer than half of Canada's high school students are graduating with Grade 12 math and science courses -- and it's costing them in the long run.

Let's Talk Science, a national charitable organization, has just released a report that argues students need to be informed that careers requiring a science- and math-focused education almost always pay higher salaries than other careers.

The top-paying jobs in Canada are in the fields of medicine, dentistry, data security, chemical engineering, banking and construction, and all require a strong foundation in both math and science.

Let's Talk Science president Bonnie Schmidt says, in fact, STEM classes (science, technology, engineering and math) are required education for most of the top-paying jobs in the country.

"We have found that whoever is categorizing the top jobs – whether it's by pay, by respect, by 'recession-proofability' – 70 per cent require science, technology ,engineering or mathematics," she told CTV's Canada AM Tuesday.

And yet, as the report found, most provinces allow students to stop taking math or science classes after Grade 10. The result is that 50 per cent of high school students are dropping those courses as soon as they can.

While those numbers are disappointing to Schmidt as a scientist, they also can mean high costs to students. "Doors can open or close depending on the decisions" that students make in high school, she points out, and some students never get a chance to try to fix their mistakes.

Other students decide to switch education plans and quickly realize they are missing important high school credits. That means having to delay their education to go back to take or re-do courses, and keeps them out of the high-paying segments of the workforce longer.

In Ontario alone, for example, the report says as many as 20,000 students that have already met graduation requirements return annually for a fifth year of secondary school, to pick up new credits or improve their grades.

The financial implications of students having to go back because they didn't stay in math or science after they were able to drop it was "quite significant," Schmidt says the report found.

"They're doing bridging programs; they're repeating high school programs. And we simply have to change the dialogue," she said.

Society as a whole also benefits when students get well-paying jobs and when they choose careers that bring them satisfaction, the report concludes. Local and national economies benefit as well.

"Science and technology drive our economy," Schmidt says. "They also drive global challenges. If you think about energy sustainability, climates change, feeding the world, getting potable water to everyone -- science underpins all of that."

In order for the dialogue about math science to change, parents need to instill a love for science and technology in their kids early to keep them engaged and fascinated, Schmidt says.

"High school can be too late. We believe we have to start in the sandbox to create curious, creative, critical thinkers," she said.

As kids get older, parents and teachers need to show students the practical and financial reasons why they should think about careers in science.

"By the time kids are in middle school, parents need to be having that conversation. Guidance counsellors need to be able to show the clear pathways leading to college and the trades. We have to share more," she said.

The science and technology industry also has to become involved, "so kids know the relevance of what they're studying for future job opportunity," Schmidt says.

"We need them to engage in the relevance of science in their daily lives."