If there is an S on the board, you can easily pluralize/singularize words by adding/removing the S and get points for both the plural and singular versions. Note that you don't automatically get credit for the singular version when you spell the plural version; the singular version must be played without the S to get credit.
Consider assigning one person to be on S duty, repeatedly picking up and putting down the S while the other players change the root word. E.g., assuming you have the right letters on the board, you can easily make POUND, POUNDS, SOUNDS, SOUND, HOUND, HOUNDS, ROUNDS, and ROUND without much movement at all.
The same idea could work for other prefixes and suffixes, too. such as -ED or -ING.
If you're going to do -ED or -ING, you only need to lift the E or I to break the long word and get credit for the root.
In the Village
Boost your passive income whenever possible. Why not earn resources you don't have to actively work for?
The passive income gets a big boost on the levels that require an upgrade item. (e.g., levels 26 and 51 for the Pine Tree).
Getting a single Pine Tree to level 51 will give more passive income than getting two Pine Trees to level 26. Consider that when deciding which objects to upgrade.
For most people, the Merry-Go-Round is the first object they'll get that gives Berries as its passive income. Just keep playing and you should get it eventually. (It probably won't be in the first 2 or 3 matches, but I've often received it in my first play session if the session lasts long enough.)
Unlock additional screens for your village so you'll have more space for more stuff.