Old iPad 2 with cracked screen - what trade-up/repair is available and is it worth using?
Apple has only had a recycling service for iPods in the past and pushes all gift cards through their official Recycling Program.

My experience is that these sort of plans don't get you top dollar, but don't require you to take any risk or spend any time to sell your old product. You should be able to determine the repair pricing for most Apple products by contacting Apple Care or visiting a retail store to get a quote. 

In this case, iPad glass isn't repaired other than at the manufacturing site - so all broken iPads go back for repair / recycle / refurbishment and you get fully tested / warranted (and potentially fully new) one in exchange.

Once you know this you can compare the repair cost with buy new cost with what you can sell it locally. Either way, this research will help you make a good sale in case the buyer has reservations - they too can always go to Apple and get a new battery, fixed screen, etc... for the repair price should they find your device not acceptable once they use it a while.