Keyboards can and should be recycled.
See e-waste
Reduce the need to buy a new keyboard by buying a good quality item at the outset. Keep food and drink away from your keyboard and give it a vacuum periodically to remove dust.
If your keyboard is in good working order, consider donating it to a secondhand/charity shop or other good cause.
There are some interesting craft projects online for keyboards.
95% of a computer can be recycled. This includes keyboards.
Take to the Whanganui Resource Recovery Centre. (Fees apply.)
Keep from landfill wherever possible.