Slide the middle section, labeled "C," so that the "1" lines up with one of the numbers in your equation on the bottom fixed portion called "D." For example, if the equation is "5 x 2" then line either the "5" or the "2" on the "D" section with the "1" on the "C" section.
Line up the second number in the equation along the "C" section with the corresponding number in the "D" section. For example, if you used the equation "5 x 2" then either the "5" or the "2" will line up with "10," depending on which number is left. This shows that "5 x 2 = 10."
Shows students why the slider works to teach the basics of multiplication. Using the same equation example, line the "1" on "C" up with the "5" on "D." Starting with the "5" count over two the "10." Because this lines up with the "2" on "C," it shows that it takes two sets of five to equal 10. Reverse the "5" and the "2" to show the students that it takes five sets of two to equal 10.
Teach students to multiply more than two numbers by working with only two numbers at a time. Use the slider to find the answer between two numbers, then use that answer with the next number in the equation. Continue until you've multiplied all numbers.