In a special Bedtime Stories Club column, run daily through the months of May and June, the editors reported significant membership gains and invited readers to write in to describe the ways in which they were living up to the terms of their pledge. Much of the membership was enrolled in large blocks, whole classrooms of students (from both elementary schools, where the "Little Stories for Bedtime" had become an important part of the daily curriculum, and Sunday schools) asking for membership at once. A significant part of the membership was writing from outside the Kansas City area, informed of the club by friends and relatives. And a not insignificant portion of the membership was composed of adults.
By May 15 (the membership had already passed 15,000) the New York Globe and Boston Globe, partners in the Associated Newspapers syndicate, were writing to inquire how they might start their own clubs. (The New York Globe would go onto have a hugely successful club of its own; the Boston Globe apparently passed).
By mid-June The Star began to suggest that the club was actually having effects on the behavior of Kansas City area animals, birds in particular reported to be friendlier and more approachable (now that thousands of children had pledged not to harm them).
On July 2, 1914, when the official Bedtime Stories Club membership had reached 38,000, the editors of The Kansas City Star provided a telling passage of how they had happened to grossly underestimate the interest of readers.
When The Star started out to enlist the friends of the Little People of the Green Forest and the Green Meadows it had an idea that there might be ten or fifteen thousand boys and girls who would be willing to take the promise of kindness to birds and animals, which is all it costs to join the club. But the ten thousand mark was passed in a hurry and in a short time there were fifteen thousand wearers of the cute red and white bunny buttons. Then marching steadily on the membership reached in succession twenty thousand and twenty-five thousand. About that time school was out, and The Star thought that now the little people would be so busy with their play that they would not remember Old Mother Nature's children, and the club would cease to grow. But Old Mother Nature's children can't be forgot as long as Mr. Burgess continues to write his stories every day for The Star, and so the club grew and grew.
By August 1 (the membership had climbed over 42,000) the enthusiasm for attracting new members had waned considerably. A 1940 profile of Thornton Burgess in the Saturday Review suggests why. The cost of buttons and certificates (and postage) had far exceeded expectations and had actually put the paper in a difficult financial position.