"busy bags" I absolutely loved this one. These are jumbo craft sticks with magnet strips glued on. Then get some jumbo colored paper clips. They can sort colors or make any kinds of patterns with the paper clips.
The bolts are graded in diameter for a more difficult exercise. Five slotted bolts and stubby screwdriver. Designed by a Montessori teacher to aid the development of eye-hand coordination and teach a practical skill.