If you are still married to your husband, then you can list him as non-accompanying but he will still have to complete the medical and also provide police certificates in order for your application to be approved. If you want to leave him off the application completely, then you will need to provide evidence that you are legally separated or are divorced (or have filed official paperwork to divorce).
Note that you will need his written permission to move your children to Canada (unless you have sole custody of all of your children).
Then you would list him as non-accompanying but still put him in the application. He will need to complete the medical and provide police certificates as part of the application.