Estimating angles
How good are you at estimating angles?
This game offers you an opportunity to improve your ability to estimate angles.
You can either play on your own or challenge a friend.
The closer you get to the target angle the more points you will score.
To change the level of difficulty, click on the purple cog.
Use the GeoGebra applet below to explore angles.
Tick and untick the box to show/hide the angle and challenge yourself to make different angles.
Why play this game?
Estimating Angles is an engaging game that enables students to improve their familiarity with angles of different sizes. By setting this activity up as a game for two people, or suggesting a minimum score, students are likely to persevere and engage for longer than they might with a more traditional angles exercise.
Possible approach
Start the lesson by asking students what they know about angles, and collect together ideas such as names of angles (acute, obtuse, reflex, right-angled) and landmark angles (90 degrees, 180 degrees, 270 degrees, 360 degrees).
Draw acute, obtuse and reflex angles on the board and ask students to estimate their size. Encourage justification for estimates.
Draw another five angles on the board and challenge the class to make better estimates than you can. Invite students to estimate each angle, and then estimate the angles yourself. Then measure each angle with a protractor. The closest estimate gains a point.
You may wish to use the GeoGebra applet below - move the dot to change the angle, and tick/untick the box to show/hide its measurement.
Demonstrate the interactivity using angles 0-90 degrees, or 0-180 degrees, before setting the group off to work in pairs. You could challenge them to score more than 50 points in 10 turns.
Keep a record of the highest score on the board. How close to 100 points can any pair get? Can anyone get an average of more than 8 after more than 10 turns? These could be long-term challenges, with students taking a screenshot when they get their average above a certain target.
Pairs could move on to angles 0-360 degrees when appropriate.
Key questions
Which angles are easy to estimate?
What strategies can you use to improve your estimates?
Possible support
Paper Plate Angles are a great way to get students to engage with angle terminology. This YouTube Video shows how to construct them. Numberless protractors are also a valuable resource: NumberlessProtractor180.pdf and NumberlessProtractor360.pdf.