Active learning ideas
Gravity and Weight explores the fundamental force that pulls objects toward the center of the Earth. Students learn to distinguish between 'mass' (the amount of matter in an object) and 'weight' (the force of gravity acting on that mass). This is a key concept in the NCCA 'Energy and Forces' strand, requiring students to use 'Estimating and Measuring' skills.
Activity 01
Groups are given a set of objects and a force meter. They must first estimate the weight in Newtons, then measure it accurately, and finally record their data in a table to compare mass vs. weight.
What is gravity?
Activity 02
Using a 'gravity calculator' or pre-prepared cards, students calculate what their weight would be on the Moon, Mars, and Jupiter. They must then 'act out' how they would move on each planet (e.g., slow-motion jumps for the Moon).
How do we measure weight?
Activity 03
Students predict what will happen if a heavy ball and a light ball are dropped at the same time. They discuss in pairs, watch a video of the experiment (or a vacuum drop), and share their thoughts on why gravity pulls equally.
Does gravity pull all objects equally?
A few notes on teaching this unit
Watch Out for These Misconceptions
Heavier objects fall faster than lighter ones.
This is a very common belief based on air resistance (like a feather vs. a hammer). Performing a 'controlled drop' with two balls of different weights but similar shapes helps students see that gravity accelerates them at the same rate, which is a powerful 'aha' moment.
There is no gravity in space.
Students see astronauts floating and think gravity is 'gone.' Explaining that gravity is everywhere (it keeps the Moon in orbit!) but that astronauts are in 'constant freefall' is a complex but rewarding discussion that can be supported by peer explanation.
Methods used in this brief
Friction and Resistance
Students explore how friction slows down moving objects on different surfaces. They investigate ways to increase or decrease friction.
8 methodologies
Levers and Pulleys
Students investigate how simple machines like levers and pulleys make work easier. They design and build their own simple lifting mechanisms.
8 methodologies