This week marked the annual Teacher Appreciation Day. And they deserve it! Society demands great things from teachers, and doesn’t pay them much in return. And yet they usually deliver. The best teachers make sure their students walk away with a love of learning, an instinct that will serve them well throughout their lives.

This year, I’m celebrating Teacher Appreciation Day, too. This semester I taught my first class at the Gabelli Graduate School of Business at Fordham University. Being a professor is quite an experience. I was both elated and exhausted at the end of every class session. And I learned a great deal from my students, too.

Teaching this class confirmed for me what great leaders already know and embrace: businesses must encourage their employees to be learners. Creating a culture of learning will serve your employees personally and professionally, and will improve your company and help it grow.

Training and development is a particularly important requirement if you’re trying to attract Millennials: a full 87% of Millennials say that personal and professional development are important factors in accepting and keeping a job.

Employees averaged 30.3 hours of training in 2012. Employees in BEST organizations used substantially higher amounts of training, averaging 57.7 hours each-;an all-time high.

Here are just a few of the reasons why business leaders should make education an important part of their culture:

1. It’s an Investment in Your Company

Paying for your employees to have access to professional development isn’t just a drain on company resources. It’s an investment in your people, which is an investment in your company. Teaching your employees will help them perform at their very best and contribute to the success of your product. Encouraging ongoing learning will also promote openness and communication within your company.

2. Clients Like It

Clients want to know that your company is providing them the best products and services available. One way to prove that to clients is to have a robust professional development program in place. It’s also an opportunity to build a better relationship with your client by offering your employees training specific to their company needs. If you really want to do client outreach, you could even invite some client employees to a training session.

3. Employees Demand It

When Millennials decide whether to accept a job offer, an important factor is what skills and knowledge they will get out of the job. They want to know how they will develop in their time with the company. So a great way to attract young talent is to be able to brag about your extensive skills and leadership development training.

4. It Doesn’t Have to Be Expensive

It can be a costly proposition to put in place an extensive training program for your whole company. But you don’t have to hire the most expensive consultant or build an entire education structure in one move. Start small, and grow it over time. Good training programs will pay for themselves, and then some, in returns. So soon, you might have the money to invest in a broader program.

5. It’s an Opportunity to Hang On to Talent

It would be great if you have the resources to send your employees to grad school, and make an agreement that in return, the employee will stay for a certain amount of time. But companies don’t do that as much any more, especially with the rising costs of grad programs and the question of how much a graduate degree contributes to success. But instituting training programs can generate just as much employee loyalty, and maybe even more. The training will be more directly relevant to their job, and it will help them as they rise through the company. It also helps build employee trust in management.

6. You’ll Learn Just as Much

I learned a ton from teaching my class. After spending time with them and reviewing their work, I have a better understanding of the Millennial mind. I know more about how to give them effective directions, and have figured out how to guide them better towards their best work. The same is true in business. Leaders can learn a great deal about their employees’ attitudes towards coaching and willingness to accept new challenges.