W pierwszym zdaniu proponowałbym zmienić szyk z "I'd like all students invite..." na "I would like to invite all students..." oraz zamiast "the party-school" napisałbym "a school party/a school event".
Drugie zdanie, które brzmi "Our target is gather cash on new equiptment sport for school." przekształciłbym w "Our target is to collect money for a new school sports equipment." przy czym zwróć szczególną uwagę na zapis słowa sprzęt - equipment.
Kolejne: "Party start in school at 20 p.m." czasownik "starts"
4 zdanie: "The main attnactions will be competitions with prizes and sweepstakes." - prawie bezbłędne, prócz zapisu attractions
5 zdanie: "In our offer will not be lacking hot meals and candy in the low price." jest trochę przekombinowane, jeśli chcesz wciąż użyć swojej wizji, to tak powinno to wyglądać
"In our offer, there will not be lacking in hot meals and sweets that can be purchased at a low price.". Natomiast ja napisałbym to w taki sposób: "Our offer will provide hot meals and sweets which can be purchased at a low price."
- Kompletny poprawiony tekst:
I would like to invite all students on a school party. Our target is to collect money for a new school sports equipment. Party starts in school at 20 p.m. next Tuesday. The main attractions will be competitions with prizes and sweepstakes. Our offer will provide hot meals and sweets which can be purchased at a low price.
Pozdrawiam.