Page sizes: In Australia, A4 are the standard (A4 = 210mm x 297mm), US use Letter pages are the closest (8.5" x 11" or 216mm x 280mm approx mm) paper. US Paper is wider and shorter than A4. So we format the margins to suit the respective local paper sizes of each region. A US Letter worksheet can print reasonably well onto A4 if you reduce the size a little, but it may be too small for some purposes and there is white space at the bottom of the page. Best practice is to simply format the page for the desired aspect ratio.
Curriculum Alignment: Some worksheets are easy to fit inside a teaching curriculum, but other more substantial ones may take some fairly major adjustment. For example, we have a range of single lesson products like the ones shown above, but our current flagship product is a full 10 week program LINK - All About Oil Pastel Unit Pack complete with assessment tools. This pack was written to align with USA curriculum standards, so it cannot simply be copied across to Australian Curriculum standards. Although there are a number of similarities between the Visual Arts domains in each respective region, there are differences in the language used and some of the emphasis on stages of development. For this reason, it would be problematic for a teacher to purchase a 'ready to go' unit of work from a US seller (or vice versa) and the time required to adapt to the different curriculum requirements would negate any time saving qualities of purchasing a readymade unit of work.
Spelling: Although there are a lot of common words shared between USA and other English speaking countries, there are some key words in the Arts that are spelled differently. One common word for example is 'colour and color'. Since colo(u)r is also an Element of Art it's extremely important to spell it according to local preference.
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