Sure, why not?? Hi there. I'm a teacher (19 years) of Older 2's and I also teach a Mixed threes class.
Most of the children that I begin with in September are trained. I have a few stragglers but for the most part, these are fast start kids that have better things to do than mess their outfits up. All of the children have to be three by January 31st to qualify for this class.
My theory is, if you can "discuss" the issue as to whether or not you use the toilet or use the diaper, then they are ready to give it a try.
I also had 4 children myself, two of each.
The boys had the most fun learning to go in the toilet. I used Fruit loops and Cheerios to get them to hit the floating target, etc. They loved to flush to see if they could beat the water down the pipe. That may be harder now with the newer toilets that flush instantly. All of my children enjoyed a variety of reading material, kept by the toilet for them to "enjoy" while concentrating on the task at hand.
One thing that you need to prepare yourself for is the frustrations of having success when a failure will occur. IT HAPPENS! Encouragemnet! Encouragement! is always best. "Next time, I know that you will try harder to make it to the potty". Boys are usually harder to "tell" you that they need to go. I tell my parents to set aside two weeks that they are going to accomplish this. You will spend a LOT of time in that small room with them. Of course, the child loves this attention. I never ask one of my students if they Need to go. I tell them that it is their turn to go. What little boy wants to put down their favorite toy and go to the bathroom?
I always let them take it with them, place it on my "potty shelf" where they can see it waiting on them and then they know it will be there when they are through. Little boys also have very little "get there" time as the sensation to go is on them before their brain can process that they need to headfor the bathroom. That is where accidents happen. A timed schedule, every two hours, works pretty well, unless they are drinking more than usual.
Teachers believe that children should be bowel trained first. If he is only urinating in the potty, PLEASE do not tell yourself or his teacher that he is trained!!
I hope this helps. Kudos to you for wanting to give this an early try. IF it doesn't work out NOW, consider giving it some time and trying it again in summer. Duct tape will keep that diaper on, by the way, if you are dealing with that issue.
Good luck,
Cathy Robinson
Woodstock, GA