Explanation: People of colour has been given less opportunities, lesser benefits and even lesser of acceptance.
Example: If you are of a darker skin in school, you are almost instantly portrayed as the weak, ill-mannered, cantankerous and irrational. Even as strong as being portrayed as 'dumb' or 'stupid'.

Explanation: Even existing decades before and now, males have been given more opportunity and generally seen as more capable.
Example: in the school activities committee, the president or the important place normally will taken by male.

Explanation: the poor students are normally been looking down at school
Example: the outfit or the stationery rich and poor students using are totally different, they normally also lack of confidence.

People have the perception from generations ago of how darker skin people act. They stereotyped dark skin people so strongly that they were so looked down upon that they never stood a chance. This perception started decades ago and have prolonged to this day, only recently having a stronger impact to equality than there had been for decades.

Gender bias is a form of discrimination against females.There are always the stereotype that male can do better work than female in the society. 

the disparity between rich and poor students can be clearly compare in visual. In  this age of time, students like to compare with each other. the poor students will feel self - abased 

We address it by accepting and by being side the people who need it the most. Many of us were born instantly privileged. Even by being born in a controlled hospital environment is a privilege. Many in other larger countries, who has strong prejudice on different race, do not have such privileges.
So by accepting that anyone is people of colour and similar to how age is just a number, a colour is just a colour. Everyone needs to have an understanding that everyone should be protected, cared for, looked after and loved.

Removing that prejudice and stereotype on genders. Allow males or females to create a name for themselves in the best possible way before we get to judge them by their gender.

Not judging the students by the wealth level of family but give the opportunity to the  poor students to show up their ability and potential. Teach the students with the correct values.