Forced colouring is a pointless activity. Really. It accomplishes absolutely nothing as far as thinking or creativity are concerned. My son is 2.10; I measure his level of interest in colouring in micro-give-a-thsis. (In the spirit of futile school activities, I made that last word a jumble to unscramble!)
Maybe a compromise is to cut down on the hoop-jumping activities he's required to do. As in, if he can complete the end of year hidden picture colouring sheet, then he gets to do problems from a folder you send in, or read the book of his choice.
The venemous tone is in no way directed at you OP, but rather reflects my exasperation with educators who feel the need to force conformity when children clearly require a challenge.
