Your interactions with your students help them determine if they want to pursue your subject beyond school. But they rarely understand what awaits them or is expected of them in college or the real-world.
So how do you help them make an educated decision to pursue a a particular direction of study?
Have them become school-based professionals in your subject area by giving them a taste of what professionals in your area of expertise do.
Teach them the skills, attitudes, habits and qualities they will need. Engage them in real-world projects and problems (at their level) and hold them to high professional standards.
They might surprise you.