Give every kid a pellet gun and $1 per toad bounty. They'll disappear quick enough.
The anti-gun bigots have won the war in Australia. No one would ever advocate such a proposal without immediately being eviscerated by the loony leftists.
They have toad hunts in Queensland and take the toads home and put them in the freezer. There they just peacefully go to sleep and it is considered the humane way to destroy toads. However, knowing how resilient toads are, they would probably hop off the moment they thawed.