Crunches challenge

Kitzzy asked about a Crunches Challenge. What a great idea! I looked and could only find challenges that strived to get 1000 per week, or 10000 per year. I'm looking for something like the pushups and C5K where it's basically a training program.

I wish I knew more about this stuff, we could make up our own. I'm wondering if we couldn't use the same formula for the pushups one for the situps? I don't know how many we should be building to, or how fast. When I was in my 20's and 30's, I used to do 100 situps every morning and also before going out. Then more during step class.

So the question is, what is the crunch equivalent of 100 pushups or a 5K? What number is hard enough to take 6-8 weeks to get there, but is reasonable for a person starting out to strive for? 200, 250? Is that enough?

Does anyone have any ideas for this? Does one of you have/know a trainer that you could ask what a reasonable goal is?

I'd love to do this if we can figure out a plan.