Your first grade students can use this 25 page booklet with pictures to practice writing simple sentences. If you have students complete one per day it can cover a span of 5 weeks. I use this for my own son. He completes one page every morning at the breakfast table.
To differentiate you could have higher level students write 2 sentences and lower level students just write one word to describe what they see.
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Making Sentences Literacy Center
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