Hello team!  I hope you all are well and tolerating the current surreal conditions we fine ourselves in.
Apologies for not being a very inspiring team "leader" but we seem to be doing our bit anyway.  I suspect many of you, like me, may feel that some number of the "challenges" are things we already do or are things that really can't be done individually by the majority of people, especially in the 6-week time-frame. Since Harley wants points, I have been treating those already-routine actions as completed or on-going challenges for which points are accrued :-) 
Another thing that you may or may not have noticed is that there are various challenges (likely in ALL the themes) that are to spend some time learning about a topic. Indeed, I think that the potential educational aspect of this whole program may be one of its greater strengths. For example, I was poking around today in the Materials theme and found an interesting link to a webpage of things one can use rather than using single-use items. I think that reading the various sources they list (plus any others that you are linked to from those and that catch your interest) could be used to meet one of those "spend time learning about____" type challenges.  [At least that's a lot easier than buying an electric car, or establishing a low-carbon cement manufacturing plant, or whatever!!!]
At least the alternating snow and sunshine today, to say nothing of the stay-at-home situation, are consistent with spending some time with the EcoChallenge :-).

Actually replaced 3 bulbs.  I was an early adopter of CFLs back in early 2000s.  I've been a little slower on LED adoption as the jump in efficiency from CFL to LED is not as dramatic as getting rid of the incandescents, but nevertheless a good improvement. 

Road 11 miles today on my bike.