How we can motivate the lower class peoples?

Motivation is an individual thing, class of the person is irrelevant. Understanding the individual is the key to motivating them. Why are they there? What do they want to achieve ? What is important in their life's ? Once you understand this then you are in a position to really motivate a person.

I don't understand your Q., I'll give you an examples of people whom classified other people into classes (Jewish, Nazism and fascism -----etc ) !!! This is a Racism. 

The best  way  to  motivate  people  is through fairness of opportunity  and  income  distribution. If you  want  to  motivate  people  so you can exploit them and their  labour then you'll  just have  to  accept  the horror  that  is  almost  certainly  coming  your  way. 

Every individual have different motivational factor........Some are after Money, some after Job satisfaction, Some after Power and position and some after social status so on an so forth....HR needs to understand this and identify what is individual's need and requirement , remember it keeps on changing ........

By engaging them in the class work with a kind of competition

To motivate them; Don't call them 'lower class people'.......How do you define classes in profession anyway? I am interested to learn.

• By giving them incentives
• By an effective performance appraisal system
• By  appreciating and making them realize the role they play in meeting your organization's goal

In my view the best way of motivation is appreciation and accountability. When the target is achieved appreciate them with words in public, small party, money incentive. At the same time make them accountable for every assigned task, any negligence, failure and delay should be punished or at least show your dissatisfaction.    

In any case motivation requires a proper understanding of the individual or the group you are looking to motivate. The idea is to see their current status and have a vision for them for improvement for the future. This can be based on different areas. The key is make them see what could be the benifits in the case of personal development and in the case of overall developement of the orrganisation. This would trigger a  sense of purpose and will drive the individual to the set goals.

If you offer "motive" to People, then can lead them forward being motivate. But every one has his/her own "motive". The most important note is that you discover "motive" of each person. Various "motives" are:

Additional payment, Increasing salary, Progressing skills by training, Promotion, Higher education, Respect, Being considered by upper level management,...    

You need to identify what makes a certain employee motivated, I am not sure if using the word lower class is right as it seems derogatory, I would prefer to use "Blue Collar Workers"

Money is a big motivation and so is kindness and respect. You cannot expect to keep waving carrots around and expect people to remain motivated, it works for a while but the consequences in the long run can be severe. A lot of this can be avoided if you put yourself and their shoes and try to think about it. Sure no organization can afford to throw money around every time but a small gift, certificate of recognition and a free meal can do wonders.

Paying their salaries on time is also a big motivation for them as they do not have to keep wondering through out the month whether when their next pay check would arrive, They can plan their expenses accordingly and this helps elevate a certain amount of stress, there are many more techniques but then this post will be too long :)