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In our science class there was an old computer and they used to let us play a sim game on it but i dont know the name. you had little people and then you had to allocate a certain number to farm, maintain the defences, build the houses, be in the army etc, then if you hadnt got it right the crops failed or the walls broke and the water flooded your houses etc. plz plz does someone know it cos its driving me mad!!!

Depends on when the computer game was released, because the description fits many life simulations.i think it could have been "harvest moon", but take a look at the link i included for more games.