A Frog in a Bog by Karma Wilson and Joan Rankin. Published by Aladdin Paperbacks.
Mallets 1 are the glockenspiels, Mallets 2 are the xylophones, and Mallets 3 are the bass xylophones.
The unhitched percussion is the guiros. If you have the frog shaped guiros, now's the time to use them - what fun! On the last beat when everyone else has a rest, end with the vibraslap. At the beginning - first two quarter notes - everyone, including voices, has a fermata on both notes, and the instruments should tremolo