median
don steward
mathematics teaching 10 ~ 16

Sunday, 22 January 2017

making a positive whole number

largely a substitution exercise
trial and perseverance, with some thought maybe


find a general form for the letters
possibly explaining why these work


Thursday, 19 January 2017

mirror multiplications

first some examples indicating that mirror multiplications do not usually have the same answers

but then sometimes they do...
253 x 64 = 46 x 352

further examples of mirror multiplications that do have the same answers












the powerpoint for this task includes a step by step calculation for 253 times 64

for mirror multiplications with the same solutions:

as an initial step to considering rules and why they work,  how can the lead and final digits of the two multiplications be made to be the same?

for the number in the centre of the 3-digit number, a grid method (expanded) representation shows how equal answers are obtained for the examples above - what is their common property?


longer multiplication pattern answers



Sunday, 15 January 2017

adding fractions procedure

the hope and intention of looping a presentation is for student's to attend to the structure of solution steps
the powerpoint needs to be downloaded for the animations to work

having introduced the procedure and indicated reasons for the steps, you might leave the powerpoint playing on the board
or use it to introduce the skill - asking students to discuss with their neighbour what is going on (and why)




Friday, 13 January 2017

equations with the as-yet-unknown on both sides





















the slides below are on a powerpoint that loops, hopefully highlighting the steps
(if it is downloaded)



Monday, 9 January 2017

Sunday, 8 January 2017

make a polygon










and another, that goes off the grid

quartering a 5 by 5 grid

hopefully being systematic, using some logic/reasoning, students can look to find all the ways to
quarter a 5 by 5 dotty grid with
(i) rotational symmetry order 4
(ii) rotational symmetry order 2
(iii) one line of symmetry

they could also find all 13 ways to half a 4 by 4 grid

the powerpoint for this