I don�t know may be let a boy come in as a vendor with things like a cards that has verbs and pictures like a boy and eating a banana and a real banana, play and real ball etc.the boys buy them. then ask them questions like what does so and so do everyday .They will say eat a banana (card) then let the boy eat the banana at the spot and ask what is he doing now and so on. Or let the boys ask you and you give the right form by emphasizing on the difference between eat eating etc.
What I do is I make three columns(if I do past here it will be two columns .I name them every day, now). In everyday I divide it into two I write They /we/you/I eat /she /he/it +eats .In the second I write am/is/are +eat +ing.SO its like eat/eats -eating play/plays - playing
Then I write a different verb and they write them in the same way after that they write sentences in the following sequence
Everyday: Subject pronoun + verb + object I eat meat. I play football. Etc
Now: Subject pronoun+ am/is/are + verb + object Iam eating meat . Iam playing football etc
I hope it helps...You could let them arrange them on the board in order with flash cards ...