CAMBRIDGE—Cabot House senior Allen Woods was sitting by himself enjoying some frozen yogurt from a plastic cup on Tuesday when the house’s eco-rep, Jenna Newman, charged him and with a wild, whooping battle-cry, tackled him to the ground. She then seized the cup of frozen yogurt and, after dumping its remaining contents on his face, crushed it to pieces and stabbed him in the chest with one of the plastic shards, screaming “NOW YOU KNOW WHAT THE EARTH FEELS LIKE!”