And the Meek Shall Inherit Kalimdor

To do this achievement you need to do the Sanctuary of Malorne dailies in Mount Hyjal.

For the Squirrel, just look for the squirrels in the trees, they will be throwing acorns at some elementals, kill that elemental and you should get the credit.

For the Hyjal Bear Cub, while on the quest: Those Bears up There - Throw one of the cubs at the core hounds that are sleeping around the area

For the Alpine Songbird, while on the quest: Call of the Flock or Wings Aflame - Kill Millagazor during the quest

For the Child of Tortolla, while on the quest: Punting Season - Punt a turtle at the fire elemental