Don't take this wrong, but you have the wrong approach. So far, you have a few tricks and you've thrown together a show. For lack of a better phrase, that is your "Product".
The problem is this. You've created a "Product" without any detailed analysis of who your "Customers" will be.
As a magician, it is your job to entertain your audience. Although the kids are not directly paying your bill, they are the "Customer". In kids shows, your audience will be very different depending on their age group. 4 to 7 year olds act very differently than 8 to 10 year olds or 11 to 13 year olds. They have different life experiences, different attention spans, different egos, and different levels of emotional maturity.
You cannot treat them all the same by pushing the same "Product" on everyone. What you need to do is create at least one show for each of the above age groups. Determine how your presentation and patter will have to change for each age group. Then, identify any "holes" in your shows that need to be filled, and go out looking for effects to fill those holes.
With that approach, you will be shopping with a purpose instead of simply collecting new effects for your closet.
Finally, be careful about doing free shows. Yes, it is great experience and a lot of fun. But, with the limited number of tricks you currently own, you probably have shown over 50% of your tricks for free. Now, what are you going to show if one of those kids' parents decide to hire you to do a show? You certainly don't want to be doing the same tricks that they've seen already.
So, if you are going to do free shows, make sure those tricks are different from the ones you will be using in your paid shows.
you can do kids tricks for adults and some adult tricks can be adapted for kids. its all subjective. i'm looking for non-age specific magic. rope magic, for example. the linking rings. you don't have to be very old to get "2 sold rings LINKED!"