Balance
reverse
EMBARKS
You can use the letters to spell the word display. You also can spell sassily.
A seven-letter word meaning serious and eager could be "earnest".
goggles, snorkle
Goggles or Costume (as in swimming costume/swimsuit) or armband(s) for little children ;)
morning? evening?
clothes
rhythms
Balance
reverse
magpies
combine them with a letter on the board to make an 8 letter word
EMBARKS
You can use the letters to spell the word display. You also can spell sassily.
Confound use thesaurus.com there are hundreds of words there.