Good pictures. I remember it well. They apparently were taken in 1969, which was the last year of the park. It had opened in summer of 1959, and at that time the narrow gauge railroad was run with one of the Monson locomotives (I think it was #3; I'd have to double check my photos) and some of the Bridgton & Harrison closed coaches, along with some of the excursion flats from Edaville.
In the two photos which were taken in front of Wakefield's former B&M Greenwood depot, you can see the steep grade leading down in the right background. That was the ruling grade on the railroad, plus being on a tight curve, so they really had to get a run for it. Running "clockwise" was much easier, and they did that at first. Once, in a sudden summer shower, the train got stuck trying to make that steep grade. They'd get about 1/3 to 1/2 way up and lose traction. The sanders were not working, so they finally backed all the way down and, using two coffee cans, the crew scooped up sand from the roadbed and poured it on the railheads. After that, they were finally able to get the train back up to the station. Everyone in the open cars got drenched, but I enjoyed the experience. Fond memories, indeed.