Final answer:
Teachers should introduce students to new irregular, high-frequency words at least once a week.
Step-by-step explanation:
In order to help students learn irregular, high-frequency words, teachers should introduce them on a regular basis. This will reinforce their recognition and assist in building their vocabulary. The most effective frequency for introducing these words is at least once a week (option c).
By introducing new irregular, high-frequency words at least once a week, teachers are providing students with regular exposure to these words and giving them opportunities to practice and reinforce their knowledge. Additionally, introducing these words once a week allows for a manageable pace of learning and integration into the curriculum.
Remember that frequency alone is not enough. Teachers should also provide meaningful context and practice opportunities for students to use these words in different contexts, such as reading and writing activities. This will help students to better understand and retain these words.