I purchased Key to Decimals last week off Ebay. They arrived today in the mail and I couldn't wait to finally see what this Key to series was all about.
Well, my first impression was...that's why it's so cheap, no bright, shiny cover, just a paper cover. No biggie. Opening up the pages my first impression was......EWWWW. They use some old-fashioned (I'm thinking 1980s IBM Selectric typewriter font) and it was UGLY. There's also hand written problems. What I did like was occasionally there were pages with graph paper background. We use graph paper a lot in math to help DS with number size and lining things up properly.
Aesthetics are important to me and apparently they're important to DS, too. I called him over to take a peek. His first comment was, "Mom, that's ugly. Yuck." However, he sat down and did three pages on the spot and got over the ugly font.
I bought the entire decimal set. After I looked through all four books page by page, I understood why this series was so popular. It's to the point, good, solid, very repetitive stuff.
I'm sold. Ugly font and all. I will be buying the geometry set and possibly the measurement.
There's no rush when teaching a child. Mastery is a good thing, and we'll continue using our math program and then following up with work in these books.