Yeah - nothing like making a game for the kids that will actually save you money.
I recently redesigned the Energy screen to include two new gauges that shows the AVG DAILY USAGE but also shows in the same gauge a graphical representation of what the AVG DAILY USAGE was for the year before. Then the second smaller gauge on the right displays the % more/less KWH daily that you are using. This helps you to know whether you can beat last years numbers.
Only problem is the heat here in Wisconsin has been extreme...so my electric bills compared to last year are nearly impossible to beat.
If you're interested, I can copy/paste the rules needed to calculate these values.