I love Pinterest! It is the easiest way for me to find recipes and ideas for school. You just type in a key word, and SO many ideas pop up! Warning: It's quite addicting, so I recommend a timer. :) I've found science experiments, sensory ideas, etc. Two of my favorite pins that I've tried are:
The Igloo -
http://johnsonwarren.hubpages.com/hub/milk-jug-iglooGingerbread Playdough -
https://www.pinterest.com/pin/167759154840553974/