Dinosaur is a 1968 public information film by Nicholas Spargo, of Willo the Wisp fame. Promoting awareness of new road signs, it shows a man becoming a dinosaur as he enters his car because he doesn't know the new signs.
Next is Safeguarding Water Supplies, a Country Code film. Made by Guild Animation it is a companion piece to When in the Country, which I wrote about here.
And finally, a Green Cross Code short, Splink, from the seventies. The rather unfortunate "Splink" tagline (find a Safe place to stop, Look and listen for traffic, wait If there is traffic, walk if there is No traffic, Keep looking for traffic) was later dropped in favour of the far lass cumbersome Stop, Look, Listen, Live.
There was also live action films as part of this campaign featuring John Pertwee, then playing Doctor Who. I think that the character in this short may be an animated version of the Play School presenter Derek Griffiths, although I'm not entirely sure...