Does the museum have lockers to put some bagpacks?

I don't beleieve so!

No

The Museum has a coat check for small bags and backpacks - larger backpacks and luggage are not accepted. The coat checks are at the main entrance on Central Park West, and at the Rose Center entrance on 81st Street.

No, they don't have lockers, but they have a coat check at the Theodore Roosevelt Rotunda and a smaller one on the lower level of the Rose Center (2$ per person, space permitting). Informations from the website.

I think not.