Any jobs

Does anyone have any job ideas for a 12/13 year old that I could do on the weekends

Are you 12, or 13?

That makes a difference.

It doesn't really matter if you are 12 or 13.

I'm going to copy this from a previous question I answered.

Babysitting
Mowing lawns
Shoveling snow
Housecleaning for neighbors
Crafts (sewing, cross stitching, crocheting; something I am getting into) then she can sell them on Etsy.com or at craft shows in your area
Pet sitting
Walking dogs

To get clients lined up, she can print fliers (if you have supplies at home, if not she can write some out, print neatly) then go door to door with an adult or older teenager to ask neighbors if they are in need of her services.