Forces in action

Objectives

1. Learn to ask questions that can be investigated scientifically.
2. Know to plan a fair test by changing one factor while keeping other factors the same.
3. Use measurements to draw conclusions and use scientific knowledge to explain them.
4. Understand that friction, including air resistance, is a force that slows moving objects.

National Curriculum

Key Stage 2, Science, Sc1 2a, 2d, 2j, 2l; Sc4 2b, 2c, 2e.

Resources

• Online activity: Forces in action (Science/Physical processes)

Teaching activities

Introduction
Give the children examples of scientific questions related to areas of science they have recently studied, e.g. “What temperature is best for germinating mustard seeds?” For each question, give the children a list of factors (e.g. number of seeds, temperature, light, amount of water) and ask them which factor they would change and which ones they would keep the same to make the investigation fair. What would they measure or observe?

Activity
Explain they are going to investigate a scientific question about forces in a virtual laboratory. Open the online activity on an interactive whiteboard. Show the children how you can set the truck moving, how you can alter the initial gradient of the track, and how you can add parachutes or weights to the track. Brainstorm scientific questions you could investigate. Choose one question, and ask children how they would investigate this to make it a fair test. Which factor would they change and which ones would they keep the same? What would they measure or observe? Arrange children in pairs or groups, with a computer for each group. Let each group decide which question to investigate, think about how will they carry out a fair test and predict what will happen. Each group carries out their chosen experiment, and if they have the time, investigates further questions. Explain that, for the plenary, they will need to explain their observations using their knowledge of forces.

Plenary
Draw diagrams to help children explain their findings using their knowledge of forces.

Which combination of factors will make the car go the furthest? Test the predictions.

Extension

Ask the children to predict and then investigate which combination of factors will make the truck go furthest, and which will make it travel the shortest distance.

Homework

Imagine that a laboratory has been set up to investigate parachute designs. What different questions could be investigated and how could you test them?