Please check my rewrites (the ones with a black dot/bullet).

Thank you!

a. The importance of your family.

Thesis: The success of a child depends on the support of his or her family.

* I think this is debatable because the other side could argue that the success of a child depends on different factors such as determination and work ethic instead of family support alone.
It seems debatable, but it's weak. How many people would really disagree with this statement, do you think? Huge numbers? Very few?? If "very few," then it needs to be strengthened.

***** I agree with you. The thesis is weak because I could not even come up with a strong argument when I try to write about this.

•Rewrite : Different from friends, family members are more frank and this candid attitude helps a person improve.

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b. The difficulty of adjusting to college.

Thesis: Despite the difficulty associated with being far away from home, college students will develop important life skills.

* I think this is not specific enough (that is, how will the important life skills influence the college students?).

Rewrite:
Despite the difficulty associated with being far away from home, college students will develop important life skills that aid them in their future careers.
Your rewrite is better, but can you make it even stronger?
• Third Re-write:
Through their difficult times in college, students will be armored with essential life skills that allow them to cope with other plights.

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c. Air pollution

Thesis: Because of the growing air pollution, the government should impose laws and regulation on factories.

*This could be debatable in that the opposing side could argue that the government should have the citizens take action (examples: carpooling ,biking,public transportation,smoking restrictions,etc) instead of the the factories,since the industries are essential to consumers.
Good --- how will you revise this one?

• Rewrite (I changed my stance here.)
While both the factories and the people's daily activities contribute to air pollution, it is chiefly the people's role,not the factories, to help reduce air pollution.

Good. I'd change it just a bit:

•Rewrite : Different from friends, family members are more frank and their candid attitude helps a person improve.

This is still vague to me. What are these "essential life skills"? If you list some (and make them specific), I'll help you work them in.
• Third Re-write:
Through their difficult times in college, students will be armed with essential life skills that allow them to cope with other plights.


Excellent!! Truly staying on one side of the fence; truly debatable! I changed some wording in the underlined part, but the thesis is good.
• Rewrite (I changed my stance here.)
While both the factories and the people's daily activities contribute to air pollution, it is chiefly the people's role, not that of factories, to work to reduce air pollution.