Fifthgrade math is a transitional math as students begin to work with fractions, decimal points and beginning algebra in the form of geometrical ideas. Students in fifth grade usually use several computation methods in order to find the answers to math problems and to advance in their own math skills.
Mental Computation

In fifth grade, mental math is just starting. Before fifth grade, students really need to write things down in order to see answers. By fifth grade, however, they should have learned enough basic addition, subtraction, multiplication and division facts to start to do simple mental math computation. The method for mental math computation is simple: Students look at a problem written on the board and solve it in their heads. They are not allowed to write anything down. As mental math problems get more difficult, some teachers might allow students to write down solutions to part of the problem. For instance, if the mental math problem is 62+146 =?, teachers might allow students to write down the answer to 62+14, and then write down the answer to that number minus 6 in order to arrive at a final answer. As time moves on, students should be required to do the entire mental math problem in their head.
Written Computation

Students in fifth grade do the majority of their computations using a pencil and paper, as they have done since they started solving math problems. Students should still practice long division, multinumber multiplication and fractions with pencil and paper computation. They also should review multinumber addition and subtraction with pencil and paper computation methods. This method requires students to write out problems and then do the work on paper. Some problems, such as division, require guessing and checking with scratch paper, as well as showing work. Functions such as percentages, fractions, ratios, complex addition, subtraction, multiplication and division should be written out in stages so the teacher can see if a student understands what he is doing. Also, if a problem ends up with the wrong answer, the teacher can figure out where the student went wrong and provide directed input for him.
Calculator Computation

In fifth grade, most teachers allow students to use calculators for the functions that they already know how to do in order to speed up the process. In earlier grades, students should not use calculators for tasks such as addition, subtraction, multiplication and division because they are still learning those skills mentally, and a calculator will bar them from learning further. In fifthgrade math, calculators can be used for the four main functions.
At this age, students should not use calculators to figure out percentages, fractions, or ratios because these are things that need to be learned in fifthgrade curriculum and should be learned first mentally and on paper.