I'm 15 years old, and I finally found a job, but my parents tell me that I shouldn't work and I should tend to my studies. See, I tend to my studies, and I just need some cash, and I give every single penny I earn to my parents for their use, taking only 20 to 30 dollars a week. Am I allowed to work, or do I have to listen to my parents? Because I heard that you are allowed to disobey your parent sin obeying Allah, but isn't working and earning money a way of obeying Allah? Jazakum allahu khayran.
I would say you should obey your parents until it goes against The Rules of Allaah Ta'ala.
And now, you decide whether you working while making your parents unhappy is obeying the rules of Allaah or not.
Besides, you may discuss about it with your parents and show them that extra-earning isn't affecting your study.
In that case, you parents might not mind over your part-time working.
Your Question seems to me kind of opinion based, but i'll try to answer it to the best of my knowledge according to my interpretation of the relationship between parents and their children or offspring.
As you might know one should obey his parents unless they ask you to do something sinful (see for example Surat al-Isra' (17:23) and Surat Luqman (31:15))! And in your case your parents don't ask you something in which you disobey Allah! But they might want your best by asking you to concentrate on your studies!
So only if you are sure that you would have spare time and the ability to work for a few hours you might consider working, but be aware if your parents then find out and disagreed it seems better to stop. As one is asked to follow the orders and respect the parents as long as they don't ask you something which is prohibited, but if you made them angry or sad that might create a gap between you and your parents which doesn't seem to go along with the view of Islam of the coherence in a family!
So i would tend to say that if you disobey them -especially after they have given you the order again- this could be regarded as a sinful act, even if your parents might need the financial help!
But to make things clear i would suggest you to clearly explain your point of view and listen to their point of view and maybe you could find a solution that fits!
See also in al-Adab al mufrad a narration qualified as hassan (as a saying of sahabi () only)
And finally this article (Arabic) about obeying parents!
Be aware that most Arabic Fatwas and the narration i quoted tend to analyze and emphasize disobeying from عقوق point of view which may mean causing harm to the parents or not honoring them or humiliating them etc. And this isn't your case!
And Allah knows best!