I'm sure the original one had fallen, but there's a nice new one. We took our kids there two years ago on a homeschool 'field trip'. We met at the Battle Road visitors center, walked the road taken by Paul Revere and Joseph Warren on their ride to raise the Minutemen. I didn't know until that trip that Paul Revere never made it to Concord. He was captured by the British and held for several hours, but let go because he happened to be unarmed. His wife had convinced him to leave his pistol at home before he left on his ride. Fortuitous, huh? When he was released, instead of continuing West toward Concord, he went north to raise the alarm to the towns in that direction.
At the North Bridge, the kids did an interactive program where the Guide gave several of the kids cards with someone's name and a quote on it. As he went through the explanation of what was happening, he would prompt the kids to read the cards. Then at the end, he had them divide into two groups, and they pretended to be the Minutemen and the 'Regulars' (British) and ran at each other in a mock battle at the Bridge. It was one of the more interesting lessons I've ever had, and I was just a spectator!