Books in A Reading laboratory book series

"There once was a farmer who had a few ducks. A few are not many. But a few are more than two. I have more than two. Now Look here, said the farmer's wife. Just how many ducks do you have?" From the book.. this book "can be read by a child in the upper first grade. Over 90% of the one hundred and forty-five word vocabulary is from the First Thousand Words for Children's Reading. "

Those who know about engines can identify them by the number and arrangement of their wheels. The Perky Little Engine is a mere four-wheeler, a switch engine, as little as they come. But there is no accounting for this one that goes off and has an adventure. It might all have ended in a haystack but for the old goat that has the wisdom to say, "Back out yourself!" This is a story for fun, braced with a little of the lore of railroading. Classroom tested for ages 7-9. Includes a Skill Builder word list at the end of the book.