Is a rabbit grass and grasshopper in the same organism kingdom?

Yes, both rabbits and grasshoppers belong to the same kingdom, Animalia. This kingdom encompasses all animals, which are multicellular, eukaryotic organisms that are primarily heterotrophic. While they belong to different phyla—rabbits are mammals (Phylum Chordata) and grasshoppers are insects (Phylum Arthropoda)—they are still classified under the same kingdom.