First, don't use all caps, it is considered to be SHOUTING.
Now, your son uses "what" tool as school? Also, which version of the tool?
Also, your Subject line was cut short, are you wanting to use PowerPoint? If
so and if you have Microsoft Office (any version) you can get the PowerPoint
update. It can usually be found in the stores for around $100 in the US. The
Office 2003 applications require Windows 2000, XP, or 2003 Server. However,
the Office XP apps will run on Windows 98 and ME and, the last I looked,
many stores were still selling the Office XP applications. Also, since you
son uses this at school, I'm guessing that your son is a Student or Teacher.
If so, you may want to take a look at the Student and Teacher Edition of
Office XP and/or Office 2003 for his use on your home computer. It includes
PowerPoint and the price is much lower. I usually see it for about $149 but
have seen it on sale for $129.