About your first tribe... did you pause your game and leave?

About your second tribe... You have to continuosly "plunk" the villager on the item you would like them to work on. It may seem like forever when you drag them on to the research table, the bush, or anything else and they don't work, but eventually they will start. The box at the bottom of your screen will say "This villagers has progressed in farming" or something like that. You will always need to drag a child on to a mushroom, they never do it by themselves, so keep your eyes peeled!

Hope this helps and I hope you enjoy all 3!