[cykros]

Good for you for being honest about your age -- I was never so virtuous.

As others have pointed out, this is due to COPPA. Use a foreign service, host your own, or get creative. Personally I'd say that hosting your own is probably your best, if not your cheapest option, as it'll teach you plenty about running a server, and ultimately, could be done on a pretty minimal spare machine (raspberry pi), if not right on your main system. You can get a free hostname redirect from a service like No-IP to access it with a dynamic IP if you're trying to access it from outside of your home network.

As much as COPPA does have some negative side effects, it's not getting repealed any time soon -- companies are still collecting WAY too much information about children, including the under 13 crowd, mostly under the same argument Pornhub tried using ("the uploader SAID the content was legal"), and then happily reaping the financial benefits of having collected it. Perhaps having a tier of under 13 rules allowing reduced use could work, but the legal system is picking its battles here, and making sure kids have access to online services just isn't a priority.