A short elementary maths tutorial (presented by Ben) introducing how to identify right, acute and obtuse angles using visual and kinaesthetic methods rather than initial measurement. Key points: right angles are corners of squares and measure 90° (denoted with a small square); acute angles fit inside an 'angle eater' and are visually smaller than a right angle; obtuse angles are larger than 90° but less than 180°. Teaching aids demonstrated include quarter-turn movement, 'Ann the angle eater' (a 3/4-circle puppet that 'eats' acute angles), and an 'angle turner' tool to show various angle sizes; the emphasis is on conceptual recognition before using protractors or numbers.
Chapters
Hi, I'm Ben. In this video, we're going to be looking at identifying the different types of angles and an introduction to it. Now, it's really important that the children have a really good grasp of the names of the angles and what they mean before we even get into using a protractor or before we even start looking at numbers. So here, here's a different angle. We can look at it dynamically or statically. Some on the board or in their books, it's static or. But a dynamic would be getting them to move. For example, I would get the children to stand up and they could move in a quarter turn. And getting them actively involved is a really, really useful way of teaching. Now, when we're looking at right angles, a right angle is always, always the corner of a square. And it always measures 90 degrees. It doesn't matter on the orientation of the right angle, whether it's on the left or around, it will always be the same. And we denote that with a little square in the corner. Again, that's a really, really useful piece of understanding for when the children later on tackle more challenging number and word problems with angles. Here we have an acute angle. So we draw that in like that. The acute angle is a really, really good way of using this. This is Ann, the angle eater. Now, it's just made from a circle folded in two quarters and then a piece cut out a corner cut out one quarter and there she is. And the angle eater only eats acute angles. So this is brilliant for the children. I've taught this in year three. And you place over like that and then you can see that if the angle fits inside it, it's an acute angle. Again, there is no need for any measuring, there's no need for any numbers. The children can see what acute angles look like. This is also really good for the children and this helps with their visuals. This is like an angle turner. So they can show 90 degrees, they can show a straight line, they can show acute angles, they can show obtuse angles. You could even get into showing reflex angles or whole turn. And again, the children can just experiment with these and have the understanding of what the different terms mean. Lastly, the one that we'll look at is the obtuse angle like that. And an obtuse angle is more or larger than 90 degrees and less than 180 degrees. They're the key facts that you need to start off for identifying angles. And from then we can build on and we can start to look at numbers.
