[Newbies] generating animations

[Ralph Boland]

I am creating an educational computer game in Squeak
in which I need to have animals (cats, dogs, birds, possibly other animals) move
mostly horizontally across the screen.  (Vertical motion is also
possible but this
would just be a bonus.)

An animal will be in a square box (not sure if boxes will have a
visible boundary) of sizes varying according to screen size.
For a 1024x768 screen the boxes would be 13x13 pixels.
For a 1920x1080 screen the boxes would be 24x24 pixesl.
etc.

The animations don't need to be great; adequate to entertain a child
of age 4-10 yrs.
I am not interested in animation per say and want to be able to write
this code with
a minimal amount of effort.

Can anyone suggest where I can learn how to do this?

If there is code that I can copy and modify that would be great.

P.S.  In the case of cats I am also in an animation of the cat
turning itself right side up from upside down as it falls.

P.P.S.  Also neat would be of cats/dogs jumping up onto a ledge but this
would just be a bonus.

I am planning for the code to be open source and free.

And pointers to code or documentation on how to write such code much
appreciated.

If any animators out there are interested in doing the animation part of my game
please contact me.

Thanks

Ralph Boland  rpboland at gmail.com