P736 CEEFAX 736 Sat 9 Apr 00:44/34        ENDANGERED SPECIES WEEK Children from primary schools across Britain will bj taking part in the Tusk Force Endangered Species Week from April 18-22.  The project, which is geared to the national curriculum, will provide a hands-on method of learning about the perilous state of many species of wildlife. Chris Packham of the BBC's 'Really Wild Show' and actor Brian Blessed will bj holding a series of family lectures at the Natural History Museum in London on April 16.  Environment index 730 Community 700 Nat Trust Read Hear CmntyInfo Religion