This powerpoint presents some ideas about how to form a sentence in the past and future tenses. I use this with my first grade middle schoolers. They really enjoyed creating sentences. When you get to the slide with the picture and word, they can form any sentence as long as it says something about the current picture and uses the correct sequence of words for that tense. Such as: the girl with the guitar has the word "NEXT" attached. The kids have to write something in the future tense such as Next weekend the girl will play the guitar/Next Thursday she will take guitar lessons/I will play the guitar next year.
I like this because it allows students to be creative and still work on the past/and future tenses. I let the kids use small individual white boards and markers as it allows groups of 3 to work together and then I say boards up for quick assessment. If you don't have white boards, you could make a worksheet they fill in or something. Or you could have groups present orally. I left some empty slides at the end if you want to put some of your own ideas in the presentation.
Enjoy!