The Sunday Crossword No 2975, Sunday 24 Dec 2017

All the best to the finalists at IXL-17. 

ACROSS
1   Tease in habitual action? Very sad (6) TRAGIC {T{RAG}IC}
4   Systems of measurement for plates (6) SCALES [DD]
10 Vegetable, bruised initially, absolute enthusiasts set aside (9,6) BUTTERNUT SQUASH {Br...d}{UTTER}{NUT} {SQUASH}

11 Roofless old enclosure, architect's last work (4-3) OPEN-TOP {O}{PEN}-{a...cT}{OP}
12 Weaving of mat seen to be most skilful (7) MEANEST*
13 Shabby article about studied obstruction (10) THREADBARE {TH{READ}{BAR}E}
15 Eccentric hobby to some extent ridiculous (4) RICH [T]
16 Run, fit and ecstatic (4) RAPT {R}{APT}
17 Most unusual to store data in tropical environment (10) RAINFOREST {RA{INFO}REST}
20 Be morose, keeping away after retirement in county (7) SUFFOLK {SU{OFF<=}LK}
21 Robbed, cold and angry (7) CHEATED {C}{HEATED}
23 Love song, terrible trial when gloomy (2,5,4,2,2) MY HEART WILL GO ON*

24 Cool and objective in test (6) TRENDY {TR{END}Y}
25 Sticky substance covering spot around mineral (6) GYPSUM {G{SPY<=}UM}

DOWN
1   Prohibited cheers with expression of disapproval (5) TABOO {TA}{BOO}
2   Mashed potato father had without hesitation (2,3,4,2,1,3) AT THE DROP OF A HAT*
3   Lack of movement, batting? Time to wrap it up (7) INERTIA {IN}{ER{IT<=}A}
5   Odd members of clan that spoil a new boat (9) CATAMARAN {ClAn}{ThAt}{MAR}{A}{N}
6   Fruit, large quota distributed (6) LOQUAT*

7   Instructions for action in raid get muddled in parts (5,10) STAGE DIRECTIONS {GET+RAID}* in {SECTIONS}
8   Speak irritably in card game (4) SNAP [DD]
9   Problem in feline gossip (8) CHITCHAT {C{HITCH}AT}
13 Tedious occasion? Half resolved to disrupt it (8) TIRESOME {TI{RESOlved}ME}
14 Put together plot involving dishonest activity (9) BRACKETED {B{RACKET}ED}
18 Covering part of disloyal revolution up (7) OVERLAY [T<=]
19 Teacher put away present (6) DONATE {DON}{ATE}
21 Extract fastener (4) CLIP [DD]
22 Study one beginning to mend fabric (5) DENIM {DEN}{1}{Mend}

GRID

In view of the IXL Finals there will be no special at 10:30 today.