I'm still a undergrad math student, and my experience in education in math is very limited, however I've been lucky enough to meet teachers that encourage students who are interested in teaching, like myself, to work with their students as support.
I have helped beginners in calculus, probability and algebra, and the common denominator, when it comes to confusions, is that the order in which the topics come sometimes doesn't make much sense to them, so they tend to forget what they've just learned and/or not use them at all after reading them. Here I have in mind only the kids who do study and really try. I keep telling them that for now these things may not make much sense, but they should see them as tools that they're biulding and saving for later, so when the heavy stuff comes they don't have to prove those things any more and can just use them as they need them.
Now, I was thinking of something based of an experience I had. Last semester I took an algebra seminar, where we studied the history of equations, and the teachers' approach was $100\%$ chronological, and based on the original texts of the authors. In that class I learned a lot of new things, but also the other things that I already knew started to make sense, especially group theory stuff, like permutations, normal groups, etc.
I'm not a big fan of teaching/learning chronologically, i.e., in the same order things started to appear in history, because I feel it doesn't make much sense, however the fact of reading the original papers, and the original questions helped me a lot to understand the motivation behind these things that we study in the classroom. So my question is, how good would it be for beginers to read selected original texts to understand new concepts?
Edit: I attached some of the texts that we covered on the seminar; it's not all of them because I don't remember all, but here we go:
- De Moivre ("De sectione Anguli", Philosophical Transactions),
- Colson ("Aequationum Cubicarum & Biquadraticarum, tum Analytica, tum Geometrica & Mechanica, Resolutio Universalis", Philosophical Transactions),
- Gauss (Disquisitiones Arithmeticae),
- Lagrange (Réflexions sur la résolution algébrique des équations),
- Vandermonde (Mémoire sur la résolution des équations),
- Cauchy (Sur le nombre des valeurs qu'une fonction peut acquérir lorsqu'on y permute de toutes les manières possibles les quantités qu'elle renferme),
- Abel (Mémoire sur les équations algébriques: où on démontre l'impossiblité de la résolution de l'equation générale du cinquième dégré),
- Galois (Mémoire sur les conditions de résolubilité des équations par radicaux),