For occupying three year olds....I have a three year old who wants to be at the table when we are doing lessons. When DD is doing math I have to stay at the table with her or #1 it will take her 3 hrs to do 4 pgs and #2 she will develop major anxiety that she "can't" do it. So, I am sitting there for awhile some days. Anway, one thing that my son has loved this last year is Lauri puzzles. He thinks the one with kids in different positions is the coolest thing ever. I also cannot say enough about Discovery Toys, and no, I do not sell them! However, they have some really awesome preschool learning hands on type activities. He has three favorites. One is Busy Bugs where you make various patterns and matches with the plastic bug things. He also loves playful Patterns which are sort of like tangrams. The other thing he really likes, DS5 likes too and that is their It's a Match game/books It has two different levels which is nice because they correspond to where both boys are at.
Some other things that would occupy 3yo for long periods. Gluing buttons (or pretty much gluing anything.) Right now, glue is on sale at
Walmart for 10cents and I bought 10 bottles the other night. I am thinking about going back and getting more. Truly, he uses a ton of glue, but I don't care. He loves his creations and he stays very busy. He glues popsicle sticks, foam pieces, pom pom balls, paper letters, pasta, really anything that will stick to paper he is up for. In fact, I made some colored glue by adding powdered tempra to school glue and he just used that on paper.
Playdough and homemade glurch are good table time activities too. He likes to play with the unifix cubes too. He also plays games like dominoes (with pictures) Hungry Hounds, (the generic version of Hungry Hippos) and several other board games by himself. Etch a sketch is another good one as are View Masters. We also have used the Leap Pad and Power Touch to keep him busy.
Water color painting, paint with water books and any kind of painting where he can paint and then fold it over will also keep him busy for a long time. (You know like those butterfly things we did when we were little. Except he paints, folds, opens, paints some more, folds etc.)
I will probably think of more, but these should give you a starting point.