Planning a school trip to London, can you help?

I’m tentatively planning a school trip to London, but am not sure where to start. My school’s administration wants me to get as many details together before the plan is approved. It’s my first time planning anything overseas, and I have to plan with kids and education in mind—that means we’re not going as ‘tourists,’ but for learning experiences. I Googled it, but if someone already knows the answer and tips, it would save me a lot of guesswork.

The kids expressed interest in seeing:
Big Ben, The Buckingham Place, Oxford, London Bridge, The Eye of London (a ferris wheel?), The Tower of London, Stonehenge, Hampton Courts, the rebuilt Globe Theater, Telecom Tower, The Mansion House, London Underground,
Westminister Abbey, Cliffs of Dover/Calais, Newton’s Apple Tree at Royal Institute of Science, and any literary spots of interest (they want to see Boudicca’s statue and as we go through the units, they will definitely want to see anything related to what they’re learning about—Canterbury, Robin Hood, King Arthur so far and more will come up).

I’ve Googled things like Literary Tours and they don’t fit what we need as a school group. I also need to figure out how we plan to get around and that will determine how many kids can go. The plan is for the second week of June.

Any ideas, tips, suggestions, information, wisdom-from-residents are welcome!!