Hi TrueDB,
You definitely can control the fonts like BlueStar4 suggests (just add ,1 for english character set in SET TEXT FONT "Arial",1 ). If you have a well designed font that looks good at low point sizes, then this method is good and easy to implement.
You can also use images, sprites, and even 3d objects to scale or resize text. The following example just scales a sprite that is made up of a sentence. You'd have to play and tweak the font and the sprite size to get it to look the way you want, but this example just shows a method...
sync on
sync rate 60
set window on
rem setup font and a string
cls 0
ink rgb(0,255,0),0
set text font "System",1
set text size 32
sync
a$="Change My Size"
rem output the string and capture it
text 0,0,a$
rem calc size of line of text
wd=text width(a$)
ht=text height(a$)
get image 1,0,0,wd,ht
sync
rem clear screen to black
cls 0
rem main - use the captured text image as a sprite and scale the sprite
increment=1
do
sprite 1,100,100,1
rem fluctuate scale of sprite
size=size+increment
if size >= 200 then increment=-1
if size <= 1 then increment=1
scale sprite 1,size
sync
loop
Enjoy your day.