unfortunately 50 usd is nothing for crypto market. you can not satisfy investing 50 usd. you should find a way to increase your investing money. you can work for a while to collect some money. or you can try some bounty campaigns if you are lucky you can earn a few hundred bucks to invest.

we all know that 50$ is not that big amount right ? and by the time you are posting this the crypto market went crazy bullish. I dont know where you are now or what you did during this past few months of bearish market.
But i think the best thing you should do first is to study how to invest. Therefore, you can able to determine where to invest your money in. And we all know that Crypto is the wild west of financial markets. you can make up to 1000x return or more here investing on undervalued projects or pretty good darn rare ICOs. You need to learn the skill of investing first dude. Before you can be able to make great returns. Learn before you Earn.

It depends on your agresivenesss my friend but i suggest you should look for additional funds perhaps... $50 can get you no where don't you think thats too small maybe you can buy Altcoin rather while it lower..but in the market that amount you'll just ending up crying to buy... So keep your money and gain more cash for you to buy btc in the perfect time.. Try investing it in small business so it timw if you have enough you have many chance in buying tokens.. Just strive my fried thats still money you have there..

It still depends on you if you want to invest if you think you are more profitable in investing because not all even $ 50 can be invested because usually in the investment you have a lot of money to spend for you to know how many value you will sell.

Since I am a busy student maybe I would put it into mining where I do not have to look over it everytime or hoard bitcoin and wait for it to rise up again and get back after a year or so.

This is a very small investment, I would recommend that you take part in bounty programs, then what you earn will be able to invest in those crypto projects that are interest to you.

$50 seems to be a low amount to engage on investments but I would like to suggest you to buy onions (deeponion). This coin has a really great potential with a great volume. 

I would constantly watch the new coins and wait for the initial listing dump to happen to buy in for short term position while waiting on the rebound.  Rinse and repeat until you're sitting on gold toilets.

Op, the amount you are referring to for investment to me is insignificant when you talk about investment in crypto currency except if you to invest it in a coins that there value is far below one dollar or maybe cent or lesser. Because as for me i don't consider such amount for any serious investment.

I would buy Coinmetro tokens. they now have an ico and a great project. The course will then rise later and everyone has a lot of profit. Do you buy bitcoin, the fees are too high to make a profit