I have based appropriate age ranges by experience with my son, starting with his age when we first tried the activity and estimations of the future.
You know your child best. Consider his or her abilities when choosing an appropriate activity. You will probably find many activities that your child could enjoy at an earlier age as well as activities that might need to wait for awhile. When I’m searching online, I tend to scan activities in his age group as well as in both the previous and upcoming age group.
Preschool (4 -5 years)
**I am also trying to backtrack to include activities from J’s early days, so those early age groups will be gaining activities over time still too. Each activity is both categorized by age group and the post date reflects J’s age at that time. (I’m backposting those infant/baby posts…. for now at least. Hopefully this isn’t too confusing to new visitors.)
Fun & Engaging Activities for Toddlers 
Thank you for outlining your organization. This will help me over at http://www.beaconvillages.com where I’m documenting activities for my son.
You really do have to get into Pinterest. That’s how I found your blog.
I’ve finally joined, but am finding it hard to transition from my own way of saving ideas to pinterest. I’ll get there I’m sure since it is extremely convenient.
I noticed that you haven’t updated in a while. Have you stopped blogging?
-Asia
My younger son is having some health issues that are filling up much of my free time. As for now, I’m needing to just do the activities with J without spending the time to photo/blog them. Hopefully things will calm in the near future so I can get back here. For the time being, feel free to roam through past posts. I hope you find them helpful!
I want to just say that I have been hunting for a blog like yours! I have a one year old son and it’s hard to find things that will keep him content along with working on any developing skills. I love all of your crafts and I hope you keep posting. I appreciate it all! Have a good day