Assassin's Creed 3 – The Homestead: Encyclopedia of the Common Man

This quest is unlike any other in the game. It is best completed over the course of the whole game. For you to complete it though you need every settler for the homestead present. By its nature, it is something that should be done over time. The homesteaders will be engaged in different activities throughout the course of the game. It is better to check each after a homestead mission to see if they are engaged in something that can be scanned. There are a number of different activities for each so check back frequently.

To check just such an instance, switch to eagle vision and look on the trainer, artisan or crafter. If they glow gold, scan them with L1/LB.

Achilles – Trainer:
Encyclopedia of the Common Man

Godfrey & Trey – Lumberers
Playing bowls, reading newspaper, sawing, sharpening tools, inspecting and loading lumber, splitting log, unloading cart

Lance – Woodworkers
With a client, planning wood, repairing a beam, sawing, sharpening tools, inspecting a fence

Warren & Prudence – Farmers
Processing flax, plucking a chicken, plowing a field, milking cows, churning butter,  shoveling hay, feed chickens, keeping bees, baking bread

Myriam – Huntress
Cleaning Musket, skinning a deer, roasting a hare, sharpening tools, trading pelts, setting a trap

Norris – Miner
Sifting rocks, sharpening tools, repairing beam, mining, filling lantern

Oliver & Corrine – Innkeepers
Trampling grape, taking measurements, roasting deer, idle behind the bar, shoveling hay, crushing apples, changing kegs, changing bottles, butchering a pig

Big Dave – Blacksmith
Unloading the cart, splitting a lot with the lumberers, sharpening tools, shoeing a horse, forging metal, adding a new metal ring

Ellen – Tailor
With a client, taking measurements, sewing, trading pelts

Lyle – Doctor
Taking measurements with Ellen, reading a newspaper, picking herbs, with a client, playing bowls