Hi Amber,
ClarisWorks can export word processing files in the then current version of MS Word for Windows format, and spreadsheets in the then current MS Excel format. You will likely experience problems translating embedded spreadsheet frames and Draw objects in CW word processing documents.
The data from CW database documents and spreadsheet documents can be exported as a tab-dlimited text file, which can be imported by most, if not all Windows database and spreadsheet applications. For those that cannot import tab delimited text, the file can be converted to CSV (comma separated values) text files. Depending which translators were supplied with the version of CW that he is using, database and spreadsheet docs may be exported to DBF or SYLK files respectively, preserving filed names and more of the formating.
Some versions of CW came with translators to save Paint documents in Windows' BMP format, GIF, or JPG formats, all of which cam be opened by one or more Windows applications.
Draw documents have no direct importers that I know of. These can be exported in the formats above, but doing so converts Draw's vector graphics to bitmap formats.
AppleWorks 5 and 6 came in Windows versions. The last Windows version, AW 6.2.2, was sold only through the Apple Store for Education, and was restricted to the education market.
An alternative, of course, is to get him a new Mac, install Appleworks 6.2.x on it, and continue with the processes with which he's familiar. AW 6.2.4 or AW 6.2.9 both work well under Leopard and Tiger versions of OS X. (6.2.4 is to be preferred until he has converted his files to AW 6 version, as AW 6.2.9 has difficulty opening many older CW files.)
Regards,
Barry