Angela, the playing with and/or collecting rocks, sticks, household objects in itself isn't something that would be of concern in a child without any other issues. Some kids just aren't attracted to regular kids toys and that's perfectly fine! In a child with issues it's something to watch for because it can be a red flag for the Autism Spectrum Disorders, especially if they are doing a lot of lining them up in lines or formations. It's important to look at the early play behaviors especially for kids who might have higher funtioning Autism Spectrum Disorders (ASD) such as Asperger's, who are riding the fence diagnostically, or who are atypical in their presentation. These kids so often are passed off as bright but difficult and miss out on early intervention.
Again, there may be other explanations for unusual behaviors but when a parent is doing the homework they want to look for behaviors such as these listed below:
2) Does/did the child
a. Favor objects for play that arent typically used as toys by their peers (such as wheels, sticks, magnet letters, etc.)?
b. Seem fascinated or obsessed by objects/topics that arent typical for kids of their age (such as
numbers, the alphabet, words, math, geography, mechanical things such as air conditioners or vacuum cleaners, things with motors, etc)?
c. Play differently with toys or household objects (such as spin them, line them up in straight lines, set them up in formations, etc.)?
d. Exhibit weak or unusual pretend play skills such as
-act out memorized scenes from books/films/TV/DVD instead of
creating situations and dialogue
-move toy trains around but not pretend to be the engineer/go places/pick up passengers
-arrange pretend people or action figures but not create imaginary situations with them or have them interact with each other, etc?
e. Display behaviors and/or routines that seem unusual or quirky?