Do you have across to the thing that you want to buy a drain cleaner, but you purchase a 100% sodium hydroxide for chemical making. And you do not how to disposal it Here it the way to solve the problem that listed down:
1.Take it into a hith quality plastic container and bring it to school. Let you teachers to dispose it .
2. Neutralizing Sodium Hydroxide. This method would require a large amout of vinegar or a stronger acid. I don't suggest you do that.
3.Except these methods, you could call your local law enforcement and let them to take caer with Sodium Hydroxide.