Adding and subtracting fractions

I’m concerned when you teach the kids to multiply 1/2 times 4 and you get 4/8. That actually gives you 4/2 which is 2. If they memorized that method then later did it with a calculator it would give them trouble.

Thank you for the clear, guided explanation of this concept. As a visual learner, it is great to see the "process" of working with fractions that is easy to walk through with the struggling student!!