Children learn that a lever is a simple machine that can give a mechanical advantage. Children set up their own lever, with fulcrum, beam and load, and investigate how far from the fulcrum different forces (weights) need to be in order to balance the load. They transfer their results to a line graph and attempt to find a relationship between the force required and the distance from the fulcrum.
Children learn that objects fall to the Earth due to the force of gravity. They explore why people don't fall off the 'bottom' of the Earth, and why the Moon dies not fall out of the sky. Children investigate the force of gravity by weighing 5 objects in grams, and then measuring the pull between them and the Earth using a force meter, measuring the force in newtons (N). They look for a relationship between their two measurements.
Children create their own force meter using simple classroom equipment. They use known masses to calibrate their force meter, adding a sensible scale. Children learn that a mass of 100g experiences a pull towards the Earth due to the force of gravity of approximately 1 newton. Children explain how their force meter works and why they needed to calibrate it before using it.
Children learn that air resistance can be put to use in devices such as parachutes. They investigate how canopy size affect's a parachute's rate of descent. They construct 4 parachutes with different canopy areas and predict and then measure how long they tale to descend from a given height. They take each measurement 3 times and calculate the mean. Children show their results in a bar chart and attempt to answer the scientific question.
Children learn that water resistance is a force which prevents an object from moving easily through water. They learn that both high and low water resistance can be desirable in different situations. Children look at 6 different situations, identify whether the object is experiencing high or low water resistance, and why.
Children learn that friction is a force that prevents objects from sliding past each other easily when they are in contact with each other. Children investigate the best surface to place on a floor to prevent people from slipping. They predict and then measure the force required to make a shoe containing a weight slide across a range of surfaces. They present their results in a bar chart and attempt to answer the scientific question.
Children learn that a pulley is a simple machine that can be used to change the direction of a force, and can also be used to reduce the force required to lift a load. Children construct a s imple pulley from 2 karabiner clips. They use a force meter to compare the force required to lift loads with and without the pulley. They record their results in a table and then transfer their results to a line graph showing two lines. They compare both sets of results and explain the advantage that a pulley provides.
Children learn that a gear is a toothed wheel. They learn that gears can work together as a gear train in order to change the speed or direction of rotation. Children look at 8 different examples of gear trains. They work out whether the driven gear will rotate clockwise or anticlockwise and whether it will rotate more quickly or slowly than the driver. If possible, they use Lego gears to test their ideas.