This challenging Grade 1 worksheet focuses on choosing the correctly punctuated sentence from four close options and adding the right ending mark to short sentences. First graders compare choices like 'the sky is blue.' and 'The sky is blue.' to see why capitals and punctuation both matter. Five fill-in items ask students to add a period, question mark, or exclamation mark to sentences such as 'How are you' and 'Watch out for the bee', locking in strong end-of-sentence habits.