Note: This does not bypass the block on the Chromebook itself, but it allows you to fetch the text content via a different protocol (cURL) that the school is likely not monitoring.
Remember to respect your local network rules—don't get in trouble over a game guide. But if you need to know whether the Rod of Discord will drop from a Chaos Elemental (it does, 0.2% chance), you now have the tools to find out. terraria wiki unblocked