Can you recommend interactive lesson publishers for checking student understanding during whole-class instruction?

Yes — here are some strong interactive lesson / formative assessment platforms that work well for checking student understanding during whole-class instruction:

1. Nearpod

• Lets you embed questions, polls, quizzes, drawings, and collaborative activities into slides.
• Great for live teacher-led lessons.
• Strong for keeping all students engaged at once.

2. Pear Deck

• Turns Google Slides or PowerPoint into interactive lessons.
• Good for quick checks like multiple choice, text response, draggable items, and numeric input.
• Easy to use in live classroom settings.

3. GoGuardian Teacher + quizzes/activities

• Helpful if you’re already in the Chromebook/Google ecosystem.
• More classroom-management oriented, but can support understanding checks with linked activities.

4. Formative

• Excellent for real-time feedback.
• Teachers can see responses as students work.
• Supports multiple question types and auto/manual grading.

5. Quizizz

• Best known for game-like quizzes, but also useful for live instruction and pacing checks.
• Students can respond at their own pace or in teacher-led mode.

6. Kahoot!

• Very engaging for fast checks for understanding.
• Best for quick retrieval and review rather than deeper constructed responses.

7. Mentimeter

• Strong for polls, word clouds, ranking, and open-ended responses.
• Useful for checking misconceptions and gathering class input quickly.

8. Edpuzzle

• Good if your lesson includes video.
• Lets you embed questions into videos and track understanding in real time or asynchronously.

9. Gimkit

• Game-based and highly motivating.
• Better for practice and review, but can be used for comprehension checks too.

10. Poll Everywhere

• Simple, reliable polling and open-response tool.
• Great for quick whole-class check-ins.

Best picks by use case

• Most versatile for live instruction: Nearpod, Pear Deck, Formative
• Fast and engaging quizzes: Kahoot!, Quizizz
• Discussion/polls/open response: Mentimeter, Poll Everywhere
• Video-based instruction: Edpuzzle

If you want, I can also recommend:

1. the best free options,
2. the best tools for elementary vs. secondary, or
3. a comparison chart of these platforms.