# [Squeakland] The clock face - Panel discussion: Can the American Mind ...

Tony Forster forster at ozonline.com.au
Sun Dec 2 16:33:01 PST 2007

```>> My mental model for arithmetic is a clock face,

The clock face is an interesting programming challenge for languages like
etoys, Scratch and Game Maker which provide good graphics support. It
provides a good context for problem solving and exploring trigonometry. See
a clock at http://www.schoolgamemaker.rupert.id.au/morethan.htm programmed
with Game Maker.

It is worth considering what kids would gain from such an exercise and how
the features of the various languages would affect the learning. How do the
languages compare for depth of learning and ease of use (engagement)? It is
only through considering these questions that Squeak can be made as good as
it can be.

Anybody want to create a clock in etoys or Scratch for comparison? Here is
the Game Maker code
draw_circle(200,200,130,true)

x2=200+100*sin(2*pi*current_second/60)

y2=200-100*cos(2*pi*current_second/60)

draw_line(200,200,x2,y2)

x2=200+100*sin(2*pi*current_minute/60)

y2=200-100*cos(2*pi*current_minute/60)

draw_line(200,200,x2,y2)

x2=200+50*sin(2*pi*(current_hour+current_minute/60)/12)

y2=200-50*cos(2*pi*(current_hour+current_minute/60)/12)

draw_line(200,200,x2,y2)

for(i=0; i<12; i+=1)

{

x1=200+110*sin(2*pi*(i)/12)

y1=200-110*cos(2*pi*(i)/12)

x2=200+125*sin(2*pi*(i)/12)

y2=200-125*cos(2*pi*(i)/12)

draw_line(x1,y1,x2,y2)

}

```