By brambles are you referring to the briars by the gong, or the vines on the hill? If you have cleared one but not the other, then you still have an area that will give you some building skill.

Also, have you built all your huts yet? Fixing huts will give your villagers skill (examining huts will not), though I'm not sure if it will give them enough skill in time before the others are too old to help.