Simplifying fractions and reducing fractions are sometimes used to describe the same thing, when in fact there is a subtle difference.
They both indeed use exactly the same process to achieve a similar result, but lets start with the subtle difference.
Simplifying a fraction, simply means to rewrite the fraction in a way that is "simpler" to use in the given problem. An example of this would be if you were asked: 3/6 + 8/12 = ?
We have to 'Simplify' the 8/12 to make it possible to add these fractions. The result would be ...
3/6 + 4/6 = 7/6
So we simplified the fraction 8/12 to 4/6 for this problem.
In doing this, did we "Reduce" the fraction? The definition of is to 'make smaller", so according to the English language we did, but according to the language of Basic Math  NO WE DID NOT!
To Reduce a fraction is to reduce it to it smallest possible form.
If we had reduced 8/12 we would have to continue to its smallest form of 2/3.
To reduce any fraction a student must be confident with multiplication of whole numbers and finding factors of numbers.
Reduce 6/12 to it's smallest form. 

Establish the factors of 6 and 12 

Eliminate common factors 

Repeat Step 1 and Step 2 if required Recognize when you have reached a proper or improper fraction in its smallest state. 
Please note, that when 6/12 is simplified it can be 3/6; 2/4 or 1/2.
When 6/12 is reduced, it can only be 1/2 (its smallest possible form).
By following these steps, these problems should not pose any difficulty for your child.
This is a very important skill to have and the only way to master it is through practice. Use the free printable reducing / simplifying fractions worksheets I have created for your use.
Don't forget to practice! You can find lot's of dividing fractions worksheets at our printable fraction worksheets section.
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