We have used Spelling Power for 4 years now, I think. You can buy it at this link: Castlemoyle
It's also available many other places. Apparently the 4th edition is the latest. We use the 3rd edition and I don't plan to upgrade.
Spelling Power Simplified
First give the Survey Test. It is a list of 50 words. You keep giving words until he gets 3-5 words wrong, then you STOP. Score the survey test, and it will tell you which Placement Test to give.
Give the appropriate Placement Test. Give ALL the words on this test. regardless of how many he gets right or wrong. Score this test and it will tell you either which level of Spelling Power to start on or to give another Placement Test.
Go to the level recommended. Ask your child to spell the words. Give words until he gets 5 wrong or until a whole group is given. It should take no more than 5-10 minutes.
We don't buy the Spelling Power record books anymore nor do we use the forms in the book. The kids write their test words in a notebook and we use a study sheet that I like better. It is slightly different from the one in the book. (I didn't compile it.) Here is where you can download it as a Word document.
Write the words he got wrong on the study sheet. He should use the 10-step method (detailed in your Spelling Power book) to study each word. This takes just a few seconds AND IS THE STRENGTH OF THE PROGRAM. (DO NOT SKIP THE 10 STEP METHOD. Especially important is the tactile step, even for older kids.) Then he writes a sentence for each word. You can also give a supplemental activity, which are detailed in your book as well, but we usually skip these.
The whole thing should take 10-15 minutes per day. You can make it take a whole lot longer (I know, because when my dh does it, he DOES make it take longer). But don't - 10-15 minutes is plenty and is effective.
If you have questions, please leave them in the comments and I will answer them.