LONDON (Reuters) -Education group Pearson reiterated its full-year profit outlook on Monday and said its new integrated structure under boss Andy Bird was helping to save costs and grow the top line.

The British company, which rejected three takeover offers from U.S. group Apollo in March to pursue a strategy of selling directly to consumers, posted first-half underlying sales growth of 6% and adjusted operating profit up 22%.

At least 100 million pounds ($122 million) of further efficiencies identified and to be delivered in 2023; accelerates our improved margin expectation to 2023 from 2025, it said.

Pearson is emerging from years of turbulence sparked by the U.S. education market moving online. It has set out a new strategy of building platforms to sell educational tools directly to consumers, not just schools, colleges or shops.

It is also expanding into the workforce training sector with recent acquisitions. It said on Monday its Pearson+ app had 4.5 million registered users.

The first-half growth was driven by its Assessment & Qualifications unit, with underlying sales growth up 16%, and English Language Learning up 22%. Its Higher Education unit, long the source of profit warnings, fell by 4%, as expected.

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(Reporting by Kate Holton; editing by James Davey)