Notes

An important note in this unit and Unit 3 - 5th grade students must be able to give their answers in simplest form. I will include a few videos on changing improper fractions to mixed/whole numbers and simplifying fractions.

Focus TEKS:

3.4F recall facts to multiply up to 10 by 10 with automaticity and recall the corresponding division facts;
5.3H represent and solve addition and subtraction of fractions with unequal denominators referring to the same whole using objects and pictorial models and properties of operations; (this will include mixed numbers and adding up to 3 fractions at a time)
5.4H represent and solve problems related to perimeter (including fractions)
5.9A represent categorical data with bar graphs or frequency tables and numerical data, including data sets of measurements in fractions with dot plots.
5.9C solve one- and two-step problems using data from a frequency table, dot plot, bar graph.
5.3K add and subtract positive rational numbers fluently;

Fractions

Our main focus for this unit will be on adding and subtracting fractions with UNLIKE denominators and use this skill in a variety of contexts.

What I have noticed over the years, is my students are able to add and subtract fractions, but are unable to simplify, or reduce, their answers. This is a skill that was introduced in 4th grade, but is complicated and needs continued practice. If students are struggling with any of their basic multiplication facts, then they will struggle with 5th grade fractions.

All answers on classroom tests, district unit assessments, and the STAAR test will be in simplest form, so it is imperative that they understand how to simplify (or reduce) their fractions.

When simplifying fractions, I teach the students to first try to identify if the fraction is already in simplest form.

If the numerator is a 1, then the fraction is in simplest form.
If both the numerator and denominator are prime numbers, then the fraction is in simplest form.
If the numerator is 1 less than the denominator, then the fraction is in simplest form.
If it is not recognizable as being in simplest form using the above strategies, then we next ask ourselves if the numerator is 1/2 of the denominator. If the answer is yes, then the fraction simplifies to 1/2.
If this doesn't work, we ask ourselves if the numerator is a factor of the denominator (can the denominator be divided evenly by the numerator). If yes, then divide both numerator and denominator by the numerator. An example would be 3/12. Since 3 is a factor of both the numerator and denominator, then we would divide both 3 and 12 by 3. Your fraction would be simplified to 1/4.
If none of the above work, then you would try to find the GCF (Greatest Common Factor) of both the numerator and denominator and dividing by that number. An alternative method is using the prime factorization of both numerator and denominator to simplify. I have a video showing this method on the video link page. Quite a few students liked this strategy, but it requires them to know their multiplication facts and have a good knowledge of prime numbers.

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