Are there anything that goes up in value that don't cost more than $100 ?

I was thinking of coins, stamps, sportscards, comic books. Under $100.

Peace

Everything from bags of sand to loaves of bread steadily goes up in price at a rate of several percent per year... it's called inflation.

stocks

if you are smart

coca cola, gasoline

US Savings Bonds

If it is an uninformed buy, pick things you enjoy, and take very good care of them, in time they will usually be worth more than you paid. If you are looking for active investment items, read all the books you can before buying anything.

Try searching on DRiP's (Dividend Reinvestment Programs). Cheap to get in on a stock without having to pay all the brokerage fees.

All the items you mentioned may go up in value but the valuations will be quite volatile and speculative in most cases. The best of the items you mentioned might be a very small gold or a silver coin (even though I suspect gold might be getting close to a interim peak soon) such as the 1 oz US Silver Eagle or the 1/10th oz US Gold Eagle. I specifically mean a common bullion coin with wide availability, not a rare coin. But I still don't recommend it.

I do not recommend you bothering with individual stocks at that investment level -- the brokerage fees will really put a dent into your return. Wait until you have substantially more money to invest before doing that, and even then don't get sucked into the penny stock game.

A much better idea would be saving up your $100s one at a time in a money market fund. When you get perhaps $2-3K, open a stock mutual fund such as an S&P 500 index fund, and start a regular $100 savings program into that fund. If you just stuck with that plan for a lifetime, you'd still be better off than many many people.