I always find the use of a ball in the classroom is a great tool. It has many uses, for beginner level teach them bounce (bounce the ball to them and get them to bounce it back), roll (roll the ball to them and get them to roll it back), and I also use a ball or a toy to teach prepositions. For a class of 20+ kids it's a good idea to get them to do the activity two at a time, show them the different preps and then get them to put the ball/toy either - on, under, next to, behind or in front of a chair or table.
For teaching colours, I use markers and pencils and get the kids to put the item into a bag. I get them to repeat what each item is as I pull it out of a bag and lay them on the floor. I then call up a student and tell them to put the green marker/red pencil etc, in the bag, all the while getting them to repeat what I am saying. They love anything interactive as you probably know.
I also use teddies and other toys to get the kids talking. You can get them to pass the toy one to the other, but they must ask for it before it is passed. For example, they must say "teddy please" and then they are allowed to hold the teddy. Or I get them to hug or pet the toy, again focus on getting them to say "hug teddy" or "pet teddy" before you allow them to do the action.
Teaching clothes is always great and I have a great activity for this. You can teach "put on" and "take off" by bringing in some of your old clothes for them to try on. I had a scarf, shirt, a t-shirt and a hat for my students and after teaching them the vocab got them to come to the front and told them which item to "put on" and "take off". If you have space another activity I do is get them to take off one shoe, again focussing on take off as they do it, then take the shoes to the other side of the class or hall, depending where you are teaching. I then yell for kids to "put on" their shoe and they all scramble to find their shoe and put it on, they love it!
I do lots of drawings for flashcards to teach the kids. If you have access to flashcards they are the best tool. You can use them in a variety of ways. Teach the vocab then use a water bottle, that is about a quarter full to spin in the middle of the class. Whoever it points to has to tell you what card you are holding up. Whether they get it right or not is not important, reinforce the correct answer and have them repeat it. They then have to spin the bottle to decide the next player.
I hope you can get some use out of these ideas. I have been teaching kindy for about 5 months and have had to continually come up with new ideas, if you have any you'd like to share please post them also!