The trick to Level 237 is to be able to build up 4 rockets and know where to use them!
Work on getting the two outer Pets down, while you build up a rocket...use the paint to help drop them and to make large groups of blocks that will get your rocket booster sooner.
The rockets then need to be used on the middle meshed blocks.
The middle column needs two swipes and each of the others just one.
DO NOT make any matches within the center square until all four of these swipes with rockets have been completed.
Once you have done these, you will see that within two moves those central pets are free!