Do you have difficulty to find quality clip art?
You may consider using this little penguin. No worry about royalty. It is a clip art I created and you are free to use it to create your own teaching products and even for commercial sales of teaching products you created. The restriction is only you are not allow to modify the clip art and sell the clip art products.
Giving credit is not compulsory, but it will be very much appreciated. You may link to my store. If you prefer to include the logo, you may get it from my blog at http://learning-toonland.blogspot.sg/2014/01/learning-toonland-logo.html
You may also be interested with the borders and frames that I have created here