CLASS: Year 9 Advanced Maths – Coordinate Geometry

TOPIC: Distance between 2 points

LESSON

Revision questions for trigonometry, pythagoras and algebra. Written on board (answers added after 5 min).

These questions are designed to increase retention of previous topics and link these to the current lesson. The questions used need to be more difficult next time, especially for trigonometry and pythagoras. I think I will stick to the text books next time (but not the one they have). Make sure instructions are explicit – state how many decimal places that you want answer stated to.

Mark homework that they should have done the previous night. Read out answers (verbal).

Took about 5 minutes (which was a good thing). Noticed students who were ‘pretending’ to mark answers – especially towards the end of the set.

2 points A & B are plotted on the cartesian plane, and the formula is derived using pythagoras’ theorom.

Need to remember to model what I want the students to draw in their book. Cartesian planes require scales, numbers and direction arrows. Asking “How do I find the distance?, can get from this introductory question, right through to”Pythagoras!” (which is were I wanted to be later in the lesson). Need to to be able to engage these students while still going through all the steps that the rest of the students need.

Modelling is again required for board work. State explicitly that A(1,5) is (x1,y1). It is important that students write out each step out in their books for future reference.

Work through an example – what is the length of each side of the triangle ABC?

This question was an interesting one taken straight from a text that I thought was interesting. I didn’t follow my step-by-step lesson plan at this point, and I drew a triangle on the board and put points on, immediately realising it was wrong. Once I asked the students to calculate the sides with the formula, they also realised this.. This was a good opportunity to teach them about the difference between a representation to demonstrate a question – and plotting it on the cartesian plane and ‘seeing’ what it looks like (and to not believe everything you see). This strategy seems to be useful for the advanced class, but I definitely wouldn’t use it for any of the others!

Modelling again – make sure correctly plotted diagram and equation are used on the board for EACH question you demonstrate.

Handout – a page of practice questions.
Extra – hand out marked assignments
Extra – collect homework books

Do not hand out marked assignments when you want students to work..

MANAGEMENT

Generally good. While demonstrating on the board used the stand still and wait approach. This worked well, although I need to work on projection and tone of the voice. Need to work on strategies to refocus a group that are doing individual work.

OTHER THOUGHTS

This was a good first lesson. Pacing was a little faster than planned, but it is still important to model correct reasoning and exactly how we want students to write it down – some students learn this way.

Need to develop strategies to refocus the group while doing individual work, as the noise level can start to creep up occasionally. The distraction of the assignment did nothing to focus them on what I wanted them to do!

Year 8’s up next!