A fixed-cutter earth-boring tool includes a first blade substantially comprising a first material having a first elastic modulus at a temperature, and a second blade substantially comprising a second material having a second elastic modulus at the temperature. The second elastic modulus is different from the first elastic modulus. A method of forming an earth-boring tool includes forming a bit body having a plurality of blades, and providing at least one cutting element on at least one of the plurality of blades. Some fixed-cutter earth-boring drill bits include a first blade exhibiting a first deflection when subjected to a load, and a second blade exhibiting a second deflection when subjected to the load. The first deflection may be a continuous function of the load, and the second deflection may be a discontinuous function of the load.