The borders aren't necessary, use of colourisation needs to be better (ie. I had lots of clashing colours!), make more use of white space, find fresh fonts, move some of the page titles around to mix it up a bit. It is amazing what another pair of eyes can tell you!
Other suggestions included: Making the owl smaller on the bird wordsearch page, giving the child more space to draw. Using the butterflies and caterpillars across a double page, and using the green panel with butterflies on, on a separate page.
I have also changed the page size so it isn't A4 as I thought it would make it more bespoke.
And after taking all the advice on board, here is what I have come up with . . .