Early Childhood Mathematics Education/Shape and line
A first suggestion for this category is to the parent or caregiver: set up a simple rudimentary woodworking shop. This will create opportunities for a toddler to experience what it means to measure before cutting, how to understand the relationship between a product (such as a set of shelves) and a diagram, etc.
Even more preliminary would be how to make a cardboard box-- open top, for visible storage of toys or other resources on organizer shelving. The only tools where safety grounding is needed are a small razorknife ("boxcutter") or scissors. Take the youngster through the manufacturing process, starting with marking and/or "scoring" a flat sheet of cardboard ("scoring" means to lay a light cut along the line where the cardboard will be folded over, usually 90°, forming the flaps which will be taped). This gives the toddler plenty of obvious understandable demonstration of how to use a knife safely-- or the sharpest point on a scissors can be used instead). Then there's cutting the right size of tape pieces, four of this, four of that etc. Alternatively the flaps can be glued and pressed together by means of a familiar office device the name of which I have forgotten.
(Apologies that diagrams I have prepared will have to wait till I have made arrangments with someone who has a scanner.)