Benjamin E.’s Answer
Teaching young children music is an amazing idea and I enthusiastically support the idea. sounds to me like you are a band kid (the saxophone gave it away). don't think playing sax for kids won't do any good. Singing along with you playing "Itsy-bitsy Spider" on the sax, or any other instrument, will help them develop a sense of pitch and make you about the coolest daycare teacher ever!
And, you most certainly put on a little mini-concert for parents at your daycare, if that's what you want to do. The parents will appreciate and it will make a great selling point for your daycare.
Now that we have put those doubts to rest, let's talk about how you are going to accomplish your goal.
First, research colleges and university with good general music programs. Most general music programs are slated at elementary and younger school kids.
Next, teach yourself or take lessons on guitar, ukelele or some other similar string instrument so that you can accompany yourself to teach songs. Break out the saxophone occasionaly to keep your cool points, but using another instrument that enables you to sing along with the kiddies is a good idea.
Lastly, be creative in your lesson ideas. Incorporate movement, simple dance, rhythm istruments, etc., to make what you are going to offer these children special.
I am very impressed that you have this as a goal. I wish you the best of luck, and if you have any other questions, feel free to ask.