When celebrating their mother's BD, Mother's Day, etc, one idea is to have the kids make homemade cards and get something special for their mom.
One project I did for Ms. Wonka after she moved out was making a pawprint of our dog and cat in a clay mold that had rocks outlining the border along with a card that had their "pawinatures" inside it to give to her for Christmas or birthday. Ms. Wonka was very touched and appreciative of this gesture.