Pond plants (oxygenating) (CT10)

I am after some oxygenating pond plants (not iris or grasses - we have that already) for a newly renovated school pond/wildlife area. Preferably native to the UK (Hornwort, water starwort, water crow foot, willow moss).
If your pond is becoming a bit overgrown, I'll happily come and take some of the weed away!