Heres some interesting things you can get your kids doing..
SCIENCE:
funology.com/science-experiments/
exploratorium.edu/science_explorer/
CODING:
For Beginners -
Scratch - scratch.mit.edu
Hour of Code - code.org/learn
csunplugged.org
Tynker - tynker.com
UNMAKING:
Head to your local e-waste business and start pulling stuff apart! We use computerrecycling.co.nz
Remember to take out any batteries and cut of any power cables and have adult supervision.
madewithcode.com
For those slightly more advanced..
codecademy.com
gamefroot.com
OR find a code club in your area. codeclub.nz
ROBOTICS:
We get our robots from mindkits.co.nz
Start a VexRobotics team at your school.. http://www.kiwibots.co.nz/
3D PRINTING:
tinkercad.com/
blokify.com/