I believe it is not wrong to depend on technology for learning purposes. Let's take an example. Will you find out ##\sqrt{29}## on pen and paper every time you need it, or will you use the calculator? I think in majority of the cases, the answer would be the second option.
I have been using Matlab (similar to Mathematica, but the Android app is free) since a long time while doing my studies. Though it's not permitted in my institution, I feel it is very necessary for learning purposes. I have used it mostly for graphing. Equation solving is another great utility that I have been using.
Now, why and where should you use Matlab/Mathematica?
- While solving a problem, if you find that you have encountered some calculations that are lengthy, but you know how to solve them, then go for such software, as it saves time. But sometimes do the calculations on pen and paper as well so as to keep practice.
- If you encounter something that you do not know how to solve on pen and paper, but you know how to do it in software, go ahead and use the software for the time being, but make sure to learn the process later.
Many people say that this will result in "technology-dependence", a condition where you will not be able to move a bit in life without technology. But I think in today's world, this is somewhat needed to save time. For example, when you are recording an NMR spectrum, in 100% cases, the graphs will be given to you by the computer itself, and perhaps you will not want to do the messy calculations, like Fourier Transforms, on pen and paper. Similarly, for generating higher order Legendre or Hermite polynomials, it is best to use software rather than solve the equations yourself. For solving Schrödinger equation for complex quantum systems, you will almost always need some software that can work with symbolic expression.
Graphing is of vital importance as it helps you to visualise what you are doing. In most institutions, during practical classes, you have to plot the data points on graph paper by hand, then draw the best fit line, and do further calculations. But things become simpler and more accurate when you perform a linear regression on the data points using software.
What I wanted to say is, in short, it is not wrong to use Mathematica for problem-solving. However, for examinations, you need to prepare yourself such that when you will not be allowed to use the software, you can still do your work. If you get into research fields, however, no such limitations will exist.